It really is a matter of opinion. I personally have never warmed up to the Ruger line of semi-autos. I love their revolvers but have never cared much for their autos.
I love Glocks. I have a Glock 21 (full sized .45) and a Glock 30 (Subcompact double stack .45). My personal opinion is they are better than the Ruger P97 in every way; however, I suggest you try one of each to see what you think.
They are all common guns. Check some of your local ranges to see if they rent Glock .45's and Ruger .45's - then you can decide for yourself.