Own or owned 3 of these 5, but have tested all 5 extensively ... for me, best ergos are: SA XD, SIG P-220, S&W M&P ... worst, by far: Glock 21, with the H&K USP not far behind (don't particularly like Glocks, but carry a USP on duty and would ... much rather not).
You should wring the most accuracy of the SIG and the H&K. As for reliability, they're all pretty proven (although the M&P doesn't have much of a track record, yet).
As for what Tom Fury noted, yeah, the S&W 4506 was one of my old favorite (non-1911) .45s, for sure ...