[carguychris]

Originally Posted by MtnMike1

I'm not familiar with Walther other than a little I've read here. Is there a specific model there I should consider?

Agreed; however, given the OP's desire for a G27-sized pistol, he/she is presumably after the P99c AS Compact, current SKU# 2796376.

Be forewarned- Walther P99 availability seems to be spotty recently. It may take some searching to find this particular pistol. I have not seen a NIB P99c at a LGS in quite some time. YMMV.

To address the original question in a bit more detail... in terms of Walther's entire lineup, including used guns, IMHO the P99 is the most likely model to fit your requirements. The PPS is not DA/SA, and the PP/PPK series has never been offered in 9mm Luger; FWIW the uncommon PP Super was chambered for an oddball proprietary cartridge called the 9x18 Ultra or 9mm Police. Compact versions of the P38/P1 family and the P88 exist, but these pistols sold poorly in the USA due to very high prices when new, and avid collector interest has driven the current value of most decent examples into 4 figures; IOW most of them are safe queens rather than carry guns.

[EDIT] The P99c AS was also sold in mildly restyled form as the S&W SW99c from (IIRC) the late 90's until the mid 00's. These were built under license by S&W in MA, and are exactly the same as a P99c under the skin. These guns can generally be picked up for less than Walthers (or most S&W's!) because collectors of both brands seem to proverbially consider them neither fish nor fowl; however, they did not sell well, so finding a good one may be an issue.