QUOTE(swgiant @ Apr 11 2015, 04:17 AM)
currently iam using Intel 520 120g ssd, want to upgrade to a bigger capacity, like 500gb. So what is your opinion between Samsung 850 evo & 850 pro ? Speed wise, evo almost par with pro but pro is much more expensive! How about the reliability issue? Since evo is using TLC which infamous for its speed drops bug.
between the two, i suggest you go for 850 pro. with that kind of money it's best to go for at least mlc nand chip. based on reviews/user comments on the internet, correction about the samsung evo speed drop thing: it only happens to 840 evo.
generally speaking, they're reliable. however for new drives, it's hard to tell the actual reliability part of the drive, because there are no prior records supporting this.
a word of caution:
DO NOT USE SAMSUNG MAGICIAN TO UPDATE SSD FIRMWARE! or rather, if there is a firmware iso files for you to create bootable dvd/usb, use that instead.
about that recent incident of 850 pro 'death' (actually it's reversible with a firmware that is available in the wild), it was caused by the convenience of samsung magician's firmware auto update feature. if you used the conventional way (bootable usb/dvd) to do the update, everything is fine. for now that new firmware was taken down after the incident.
with all that cleared, now what's your usage? if it's for common usage or gaming only, i think you should go for mainstream drives instead. normally you don't feel significant differences between mainstream and performance sata ssds. (the differences are there, but you might need more than common usage to feel it)