OK so I have a ASUS p8z77-V LK mobo 2 sata 6 ports and I was thinking its time to upgrade from this seagate Barracuda 1tb 7200rpm 32mb cache brick to something faster its holding me back ;)
which one of these will give me best $$$ to performance I will be doing nothing but gaming.
I would actually recommend the mx100 from crucial. It is their drive with their new nand http://www.newegg.com/Product/Product.aspx?Item=N82E16820148820&cm_re=mx100-_-20-148-820-_-Product
I have had the first drive you listed (corsair force gt 120gb) for 2.5+ years now and I can vouch for it as a speedy drive. It has lasted well too. The only thing I would suggest would be to get a sata cable with a friction fit. The corsair drive does not have a place for the metal clip on a lot of sata cables to latch on to so they will have a loose fit. It's not a major problem, I have had a loose cable for the last 2.5+ years without any issues, I just don't like that it doesn't have a perfect fit.
Update: holy fucking shit this is soo fast I boot in 7 seconds now. wow would I have the same increase if I got another for say high priority games like BF4 and other pvp games?
If you install a game on an SSD, it should start up very, very quickly. You won't see an increase in FPS though. It won't be as dramatic as when you moved your OS from your HDD to SSD, but it's noticeable.
Also if you have any heavy programs, for example I use Maya on a daily basis. The boot time for Maya is insanely fast. Almost instant. As to compared on my HDD it takes several minuets. But yeah as far as games, only load times will be faster.
I do recommend putting BF4 on your SSD if you have space. If you have all 4 DLCs it is 47 GB though. The maps generally load much more quickly; I had it on a 5400 RPM drive and it would usually load in 2-3 minutes, whereas with an SSD it's probably more around 30-45 seconds depending on the map.