How good is i7-2650QM processor?

buying a dell xps 15 latop with 2nd generation Intel� Core i7-2630QM processor 2.00 GHz with Turbo Boost 2.0 up to 2.90 GHz.does it seem like a good deal??... originally it was with 1gb nvidia , but i upgraded it to 2GB NVIDIA� GeForce� GT 540M graphics with Optimus.. there are cheaper i5 processors with 2.5 GHz with turbo boost up to 3.7 GHz.. is i7 with 2.00 GHZ better than i5 processors with 2.5 GHz with turbo boost up to 3.7 GHz??? I am a medical student, so no idea what the practical implications of this lingo are...