Topup if you're able to, since the capacity, performance/price ratio is lower.

Try ask lingloong from garage sales, his Intel 530 240GB should fit your bill, may topup bit more to cover the postage though.

What's your aim between those two?
Performance or warranty value?
If performance then Samsung EVO, warranty then Intel.
Real world usage won't notice any differences between those two, only when you goes into specific task like loading lots of files or any IO intensive programs.

Comparison: http://versus.com/en/intel-530-series-240g...g-840-evo-250gb
Take it with grain of salt though... just follow your instinct..

If you can wait, there're some sifu here with Samsung EVO that had issue with performance for old data (more than few weeks to months), Samsung already came out with firmware fix but still need times to determine if the fix will works long term.
If you can't wait and do not want to take the risk of bad firmware (hopefully it's not ) then go for Intel, the firmware is one of the most reliable so far, haven heard of any issue regards their firmware.

MLC has better endurance than TLC chips but as tech grows, it improves with how controller and firmware works to minimize the wear level in each chips, Samsung uses their developed software call Magician or whatever it is (lazy to Google ).
Intel however has their own R&D and they have good history of developing chipset and firmware (look at all the Intel mobo...).
Samsung also developing many NAND chips for OEM and Enterprise so their storage chips is very good, now the only thing left is probably their firmware development, of which I'm looking forward to.
It's been long since I heard/saw SLC, even more Enterprise are now uses MLC, and Samsung trying to pushes the TLC into Enterprise market.

If you don't do bulk copy all the time (copy tons of files), the sequential speed from SATAIII is not so useful, random 4K read/write is much important, just make sure you're on native chipset (Intel usually preferred for Intel mobo) for optimum performance.
Benchmark wise there's only minor difference from SATAII to SATAIII in terms of random 4K read/write so you don't have to worry if it slow till "poke"

My plans for my laptop is 240/250GB or 480/500GB in the future and install my current (120G) SSD to my old desktop (still using SATAII) for faster OS and games load. That will be an unknown future time

I was in the same condition as him before when I was using my previous Dell Studio 1555, even though it's Scorpio Black, it will become that slow after half-a-year. I use hibernate almost all the time when I was on my previous laptop, just to shave off a minute of boot up time, it was a terrible experience when I think back; how the hell did I had such patient?
Now my SSD is been running for more than 9 months with Windows 8.1, shows some sign of slowing down but still capable of booting fast (worst is around 25 seconds), SSD is really amazing. Putting more poison to newbie...

This, you need to read the full manual for your mainboard support, the full hardware support should includes all the ports, switches, and jumpers for your mainboard.
Otherwise, you will have to find one of the Internet for the complete hardware service manual.

Ok, found this link to servicing manual for your model, but I'm not guarantee it will the very same mainboard model however.

2-4 minutes? You're patient enough. An SSD helps..

crucial drives are usually at lower ends in terms of performance benchmarks. however what matters the most is still the speeds when all these drives are in steady state. for real world usage, this speed in steady state is good enough for us to have a good user experience (seriously, you will not feel obvious slowness in general)

oh the reason why i said mx100 512gb is because the die count in a ssd can affect speed (parallelism). the more the die count the better.

all in all just get one based on your budgets. unless you have to rely on high-speed storage to earn a livings, mainstream ssd's are usually good enough.

if you want it now, just grab the best performance/value drives available to that budget.

or, you can save up some more and grab the same but with higher capacities. (480gb and up) for people who have tight budgets, i think this makes more sense than going for so-called the best. this is because that 'the best' tag can only last for a year at best. after that, you are still left with the fact that the capacity is only good for OS-only drive, if you considered stuff like overprovisioning and all.
so i assume that you already have a compatible hdd caddy with you, yes m6s is fine. (in general a 7mm or 9.5mm should work, depending on the caddy) however, it's also better to check if the manufacturer releases mac-compatible firmware updates.

no idea lol maybe you should find that out

SSD nowadays are price according to their respective performance, warranty seems to be the 2nd thing that consumer look at right now.
The 730 will be tad expensive, but slightly faster, and also has better features such as Power lost protection, good for desktop without UPS.

Easy spoilt as in? Physical abuse? or Benchmark Write abuse?
If physical abuse, it'll depends on the severity, if just a knock or vibration won't be able to kill it (even under operation), if you use hammer or dip in water then it'll void the warranty right away.
Benchmark is usually done few times to confirm your performance optimization, other than that, you won't need benchmarks all the time, so Write cycle of the NAND should last you decades to come with normal daily usage. Downloads and BT will be another story.

my mobo only support SATA2, so to be honest, neither samsung/intel will have much difference when it comes to performance because you're already bottlenecked by the interface.

I personally went for samsung because of the price and also due to the hype.
i was affected by the firmware issue but again, it wasn't that noticeable because performance in regards to SSD is barely noticeable in real world applications unless you're looking at synthetic benchmarks all day.

i gotten the 840EVO 250GB since march, until now no issue (also updated the firmware/fix applied)

gotten another 840EVO 250GB for my sis's gaming pc just last month which is also affected by the old file issue, firmware/fix also applied and performance is insane especially when the pc is on the latest windows 8.1 + RAPID mode.
transfers are in the gbit/sec (lol RAPID) and windows boot up/shutdown is in the 3seconds +/-
everything is snappy as hell lol

eh sorry, should be GByte/sec lol...
RAPID is just absurd at times when it comes to benchmarks

but on real world application, loading windows in 2-3 seconds (heck the BIOS POST screen takes longer time ROFL!) and virtually ANY application loading the moment you double click it... is just amazing

my opinion:
if you're going to be sitting on that SATA2 3bit for long, and not using windows 8.1, maybe intel would be a better choice just for the warranty and firmware reliability.

if you're upgrading mobo, and/or already on windows 8.1 with decent memory space and can allocate bigger over provisioning, samsung 840evo 250GB will be a very fun drive