Bad news is, when I do some checking with both GT 610 and HD 7550M, I've found out HD 7550M isn't as strong as I thought. Both graphic card would perform badly in some games like FC3, BF3, Crysis 2,3 ... even in lowest settings.
Therefore, I would recommend u AMD laptop at $500-600 which could bring better performance than these two i5 laptop. I admit these i5 laptop are strong in CPU but the GPU may let u down in struggling with low fps.
These laptop, I think, would provide enough graphic power to keep frame rates: http://www.newegg.com/Product/Product.aspx?Item=N82E16834215663
or this: http://www.newegg.com/Product/Product.aspx?Item=N82E16834215974