SiG has 2 poly's currently available.
I've fired the SiG P250 in .40 as well as 9mm but chose to own a SiGPro 2022 in 9mm (also available in .40 and .357SIG - no conversions available between calibers in this model series). It simply felt better in my hands and won out (after several years of "test driving") over all the polymer frame handguns I tried. USP, M&P, Glocks, P2000, XD and all the rest. Some had features I liked, many had features I did not. None of them had "everything" for me to consider it a "be all, end all" epitomy of polymer frames. The SP had the best overall fit and feel for my hands, came in a caliber that is my personal preference (and most proficient with) in 9mm and I got a sweet deal ($) on a German produced French contract overrun.