Out of those the 650TXV2 is the best. The cables on it are reasonably long, so shouldn't have any trouble in a case that mounts the PSU at the bottom, altho of course it depends on the case.
The OCZ ModXStream Pro 700W has fairly short cables only ~45cm to the first connector, so is less suitable for a bottom mounted case.
Here is a good modular one:
Thermaltake Toughpower XT 775W 80Plus Silver $120 ($6 shipping)http://www.newegg.com/Product/Product.aspx?Item=N82E16817153127
BTW i7s (certainly the Sandy Bridge i7) aren't always the best option for gaming, as hyperthreading isn't really utilised by games and the money saved by getting an i5 could be put to better use.