"They are both easy to field strip. For some reason, the Glock doesn't get as dirty. No idea why"
LOL, very true. My Sig, Glock, H&K USP9, CZ75B and Hi-powers that I used to have as of nine months ago, cleaned up much easier than my Beretta 92FS. I am a stickler for cleanliness in my firearms since my army days and always find myself spending extra time scrubbing the barrel rails. Those nooks and cranies in the barrel lockup double the time as compared to my other pistols.
There are things such as the afformentioned cleaning and the complexity of changing some springs like the firingpin and spring that get a curseword out of me here and there, but I shoot the 92FS soo well. I am more accurate with it than the others and the hand filling grip really makes fast rapid fire strings very controllable. Last year I decided to downsize my collection of 9mm handguns to one fullsize and the Beretta won out. They are all in the same ballpark, but the Beretta won out due to how well I shoot it and the fact that I was more invested in it (magazines, parts, holsters....etc).
I do want another Glock 21. It is, IMHO, one of the best .45s out there.
The trigger pull is probably the reason some don't shoot the Glock as well even though the platform is very capable of equalling the others. Hickcock45's Glock videos on YouTube prove that it can perform just as good. just need to get used to the trigger pull is all (which isn't bad).
If I was starting over and was going to choose one to really concentrate on, i might choose the Glock 17 for it simplicity and ease of changing out worn parts.
Both are good choices so find a range and rent both like others have said.