I have experience with all three 9mm platforms, having owned all three at some point and retaining those that suit me best.
My observations from my professional LE experience with these 9mm service sidearms follows:
The Ruger P95, while quite reliable and comfortable to shoot, is a strong, massively constructed handgun and the price to be paid for those qualities is that it is a rather bulky sidearm that tends to be somewhat inconvenient for the purpose of concealed carry.
The slide itself is relatively trim for a Ruger, but the sights, safety lever and slide release/disassembly lever all seem conspire to contribute to its dimensional girth and make it a little ungainly for concealed carry.
As an open carry service sidearm, it is certainly acceptable since its structural profile is of lesser significance in this mode of carry.
While not a "top of the line" selection, its accuracy and operation were acceptable.
Since the vast majority of my time is spent carrying concealed these days, the P95 saw such infrequent employment in that role that I decided to part with it and recoup the capital that I had in it for use in another pursuit.
It was a fine gun overall, but not optimally "streamlined" for the purpose of concealed carry.
It is the least expensive of the three and if money is an issue, this is the best gun for the money.
The Sig-Sauer P226 (also in 9mm) is a well constructed full-size service handgun. The P226 is also a large service weapon, moreso than the P95 both in its mass and its physical dimensions.
Its trigger in either SA or DA mode was superior to the P95's in every aspect (smoothness and consistency) and was highly conducive to excellent accuracy as well as short "split times" on follow up shots during qualifications and training drills.
The lower frame/grip of the P226 tends to be a bit "broad across the beam" and while it lends itself to increased comfort during firing, the penalty for such an attribute is that it is fairly difficult to conceal properly under lighter clothing. With a little effort and attention to clothing details, it can be concealed, however it demands constant vigilance in that regard. While it still resides in my gun safe as my most favorite service weapon due to sentimental reasons, I wear it rarely these days.
It is also the most expensive of the three guns discussed herein.
The Glock 17 is the lightest and most dimensionally appealing of the three.
At ~25 ounces, it is lighter than the Ruger P95 by two ounces and the P226 by eight ounces, gives me two more rounds than the P95 and one more than the P226 and a grip geometry that fits my hand better than the P95 or the P226. In addition to this, the slide presents a much smoother profile and while not much smaller than the P226, conceals with a lesser degree of required vigilance even in warmer weather where lighter clothing is the "uniform of the day".
I don't particularly care for the polymer sights that Glock provides with the 17 since they seem a bit "fragile" for a serious defensive CCW piece, but it is an issue that is easily remedied with any one of the numerous "after market" sights available for the gun. My choice was to replace them with Heinie Standard Sights since they provide an extra .400"/1.016cm of sight radius over the O.E.M. factory sights due the configuration of the Heinie's rear sight.
On a good day at the range, I can usually shoot 3" groups at 25 meters with the G17 and hit an 8" circular steel plate at 50m on command with my preferred carry load.
As the G17 can still be purchased with a little searching for $550-$600 it is the 'mid-priced' gun of the three and worth every penny.
While I strongly prefer the Glock 17 over the P95 and the P226, any of these guns will do the job. I've carried them and bet my life upon them and would carry any of them again without hesitation.
GS