People either like this model or hate it. Early on, there were problems with dry-firing without a magazine in place. This caused damage to the magazine disconnect safety system. The manual on early production models made no mention of this. The newer manuals have the following warning:
CAUTION: Dry firing your RUGER® P345TM with the magazine removed may result in damage or unnecessary wear to the firing pin blocking mechanism.
It is unclear to me if Ruger made any changes other than change the manual or not. In any case, this problem seems to have gone away - maybe through education and nothing else.
Others have had problems with feeding and generally blame the 8 round magazines with the steel follower for that. Many don't like polymer frames and even more hate the internal lock, magazine disconnect and loaded chamber indicator.
Now that the disclaimers are out of the way, I will tell you my experiences with, and impressions of my KP345PR.
Comparisons of size and weight:
Currently I also have a KP90D and a KP97D, as well as 5 other P-Series guns. The 345 is a good deal slimmer than the 90 and a bit shorter overall. The 345 has a 4.25" barrel and the 90 a 4.5" barrel. The 345 is also a bit slimmer than the 97, but has the same approximate length overall. The 345, 97 and 95 all share the slim safety or decocker levers, unlike the 90 and other P-Series. The slide release lever is also the most slim of the all the Ruger series. The slide of the 345 is the slimmest P-Series to date, as is the grip frame. The following weights are from Ruger's specifications: 345 = 29 oz, 97 = 31 oz, 90 = 34 oz.
Ergonomics:
This is really subjective, but I will give my 2 cents. I have fairly small hands. (I wear medium size men's gloves) For me, this gun just feels right in my hands. The back plane of the grip has a gentle curved contour, somewhat like a 1911 with a curved back strap. There are also subtle indentations in the upper left and right grip panels that help position the gun in my hand and make the reach to the trigger for a double action shot slightly shorter. The magazine release is a round button like a 1911 and many other semi-autos. This is more aesthetically pleasing, easy to reach and easier on the thumb than other P-series pistols. The safety or decocker levers are ambidextrous, slim, but easy to manipulate. The slide release is right at your thumb but doesn't get in the way when I'm shooting.
Shooting Impressions:
This gun balances nicely in the hand and points naturally for me. The 3 dot sights are adequate except in low light conditions. For this type, they are as good as most and better than some. Felt recoil for me is no more noticeable in this light gun than it is in my 90 or 97. In fact, I personally find it the most comfortable to shoot. It has the best single and double action trigger pull of all my Rugers - smooth, not much creep and a clean let-off. This is obviously not a match grade semi-auto, but mine shoots very good. I have a target with a 10 yard 5 shot group hanging in my office that you can cover with a nickel. My eyes are not good enough any more to give it a fair test at 25 yards. It is more accurate than both my 90 and 97 and shoots better for me than my 9 mm's and .40 S&W.
Reliability:
With only a 1000 rounds down the pipe, I can't judge long-range durability. So far it has been flawless with factory ball and hollow points, and my reloads with hollow points and lead semi-wadcutters.
I know others have had significantly different results with their P345 Rugers. I can only relate my experiences and they have been great. I've owned or own Colt, Star and Taurus 1911s, Browning and FN Hi-Powers, Beretta and Taurus 92 style 9mms, a Springfield XD, Kel-tecs in a couple of calibers and 10 different Ruger P-Series. This is my all time favorite semi-auto.
Tom
Here is a link to my previous post on this subject:
http://rugerforum.net/topic.asp?TOPIC_ID=1280