You will see negligible difference between a 3gb or 6gb drive on either type of sata port.
The real benefit of a ssd comes with random i/o, and that is very good regardless.
My pick today for reliability would be between samsung or intel.
I agree, 60gb is a bit small, it is ok for the os and a game or two.
Intel currently has some nice rebates on their 320 series drives. 80, 120,160gb.
Your cost will be about $1 per gb.
How about the 160gb drive at $155?http://www.newegg.com/Product/Product.aspx?Item=N82E16820167054