Since the new Samsung 850 Series is out the prices on the 840 Series went down a little.
I myself use a 840 SSD (http://www.amazon.com/Samsung-Electronics-EVO-Series-2-5-Inch-MZ-7TE250BW/dp/B00E3W1726/ref=sr_1_2?ie=UTF8&qid=1411467966&sr=8-2&keywords=samsung+850+evo) and i store my main games on it as well as my OS. It performs really well with writing and reading speeds on the higher end of 500mb/sec and after 6 months of high usage it is still in 100% health.
Intel's 730 (http://www.amazon.com/Intel-SERIES-2-5-Inch-Internal-SSDSC2BP240G4R5/dp/B00IF4NGEU/ref=sr_1_1?ie=UTF8&qid=1411468191&sr=8-1&keywords=intel+ssd) Series is also a prime choice, they are known to be highly reliable on the long term, but are a tiny bit slower than Samsung (a tiny tiny bit slower). They also offer great looks and you can proudly mount them on the side of your 5.25" bays
If you need cheaper choices let met know.