the best video player for the samsung galaxy s3 with exynos cortex-a9 quad core cpu is....
mx player pro!
rated on a score from 1 to 10, 1 being worse, and 10 being best.
performance: 8
gui: 9
features: 8
codecs: 9
subtitle support: 9
performance is good but there is a little sluggishness a bit, but not enough to make it a pain watching. this is better than all the other alternative android video players i've seen. By the way this result is when streaming from my QNAP TS-659 Pro using Plex Media Server QPKG, via my linksys e4200 wireless N router, to my Samsung Galaxy S3 smartphone, via bubble upnp .....
gui is excellent, i have little to no complaints. the interface is easy to use, aesthetically pleasing and practical. it has toggable audio and subtitles. you can also switch between H/W or S/W quite easy as well.
lots of configurations in settings. for codec support i've thrown my usual media such as 1080p mkv dts media at it, and it works. however keep in mind dts audio doesn't work for the newer versions of this app

i watch a lot of japanese anime, so subtitle support especially for ssa is important. it has good subtitle support
my mx player pro was crashing so i downgraded to "MX Player Pro v1.6f (NEON)" + "MX Player ARMv7+NEON Codec 1.6f". This particular version also has the dts audio codec before it got removed in the next version due to licensing issues
it's rock stable, and the most intentive 1080p bluray mkv video i got can play using the s/w fast mode in the player.
QUOTE
MX Player Pro Changelog
1.6j
Fixed crash on tablet devices and settings screen.
1.6i
Added support for Android 4.1 Jelly Bean
Added support for MIPS CPU having MIPS32 rev.2 instruction set.
Fixed some network playback errors.
1.6h
Fixed audio playback error with some codecs.
1.6g
Added file deletion menu on playback screen.
Changed not to show UI while loading video.
Fixed .m3u8 playback error.
Removed DTS audio codec due to license issue.
1.6f
Added a reset menu to clear all user settings.
Added an option to resume only the first video.
Added an option to adjust interface auto hide delay ranging 1 to 10 sec.
Fixed video control panel interface disorder on some devices.
Fixed disabled volume key while input locked.
1.6e
(Pro) Fixed frequent license checking.
(Pro) Added license status display on the About screen.
Improved input lock and added the ** Lock.
Improved headset key input handling.
Added an option to disable http/https video URL association.
Added an option to apply selected aspect ratio to all videos.
Added 'Use system default' to screen orientations.
Added an option to display remaining time instead of elapsed time. This can be easily switched by touching elapsed time text on the right edge of video progress bar.
Added an option to add Quit button on the menu. Unlike back and home button, quit button completely terminates applciation.
Added an option not to interrupt current playback of other players.
Added an option to hide previous/next video button.
Fixed swiping to incorrect position on SAMI subtitles.
Fixed 10bits videos playback error with H/W decoder on some devices.
Fixed stopping playback when seeking video position on some devices.
Fixed not excluding videos having unsupported file extension.
Fixed incorrect CPU type recognition on some devices.
Fixed bitmap subtitle handling error on Kindle Fire.
1.6d rev.1
Fixed conflict with some security softwares.
1.6d
Added an option to select NEW tag display period of the folder/video list.
Fixed stopping playback when seeking video position in some devices.
Fixed video playback error in 1.6c for some videos.
Fixed battery/clock background color drawing error.
Fixed resuming to incorrect playback position.
1.6c
Increased maximum volume of S/W audio to 200%
Improved text subtitle drawing speed.
Improved integrity checking of internal modules.
Added options for on-screen elapsed time, battery/clock display; Background color and Bottom placement.
Added support for .mov text subtitle.
Added shuffle/loop option. (Long click the next video button)
Added border thickness option for text subtitles. (except SSA)
Added fade-out option for subtitle text; Turn on this option to see fade out effect for disappearing texts.
Changed drawing order for bitmap/ssa subtitles to be placed above subtitle background.
Changed SSA default font option to be a global option.
Changed playback screen menu.
Made slightly darker for 0 brightness level, but if your hardware supports it.
Made minimum seek speed lower.
Made the previous video button work smart; The previous video button either opens previous video or restarts current video from the beginning depending on playback position.
Made default H/W subtitle of some ROMs not to be displayed. This can be reverted by an option on settings screen.
Fixed file scanning bug.
Fixed playback stopping bug after completing video seeking on some devices.
1.6b
Fixed network play error.
1.6a
Added font folder selection menu on the settings window.
Added an option to ignore font specified on SSA script but use default font instead.
Added an option to disable folder/video editing menu.
Added SSA subtitle display size scaling option.
Improved S/W audio processing.
Improved slowing down problem when internal subtitle is used.
Fixed subtitle HTML color tag handling problem.
Fixed subtitle loading error related to internal subtitle.
Fixed backlight handling error when lock button is used.
Fixed ANR error when playback screen is closed while connecting to remote host.
Changed playback screen menu.
1.6
Added support for DVD, DVB, SSA/** subtitle tracks. (But subtitle scrolling is fairly limited with embedded subtitles. Also Teletext subtitles are still not supported.)
Added support for full styling of SSA/** subtitles.
Added support for Ruby tag. (Only useful with East Asian texts)
Added option to select subtitle folder.
Added network subtitle file loading with http:// playback.
Added support for loading previous/next videos with http:// playback.
Added support for mms:// playback
Added support for playing Gmail attached video.
Added support for .m3u(8) playback.
Added option not to touch main button backlight to avoid Galaxy Ace/Geo's backlight error.
Added selection window between resume/start-over on playback startup.
Added option to keep screen on even after playback stopped.
Added option to change seeking speed by screen swiping.
Added keyboard shortcuts on options menu.
Added battery charging indicator.
Added battery/clock display option on tablet devices.
Added option to limit video zooming size on H/W decoded screen.
Added log sending function. (MX Log Collector is required.)
Added video zoom menu (Long click the video zoom button)
Added rotation lock menu (Lock click the lock button)
Added option to show current progress when locked screen is touched.
Improved network URL input window.
Changed video/audio synchronizing logic on S/W decoder.
Fixed incorrect aspect ratio of H/W decoded screen on Android 4.0 devices.
Fixed seldom losing internal states.
Fixed playback screen display error on some devices.
Fixed abnormal termination while loading video thumbnail.
Fixed .srt parsing error having display position.
Source:
https://sites.google.com/site/mxvpen/features/changelogoddly enough this version is better than the most latest. it's not just due to lack of dts, but that in the newer version i am crashing for some reason .... whereas this older version doesn't o.O;
PS: as mentioned above, you won't be able to get the MX Player Pro neon + codec 1.6f because it got removed due to licensing. but if you bought the app legit, then there otherways to get it without feeling guilty about how you got it

cough cough...
This post has been edited by Moogle Stiltzkin: Aug 1 2012, 02:47 AM