this might sound like a cliche, but it really comes down to personal preference. i've bought multiple mice & keyboards throughout my gaming years, and i'm pretty sure any serious gamer has too. i'm currently using the 2nd gen G15, which i like but have never used the macro keys and the lcd app uses up too many resources i have disabled it. in my case, i would have been perfectly fine with a kb with less features.
as for a mouse, i prefer a thicker feel MS sidewinder vs thiner logitech G5.
go to a store like bestbuy where they have different models on display and get a feel for them.