Medic,
A while back, I went through the same thoughts and considerations you are going through. Before then, I had always shot a Colt Series 70 1911A1, and was very happy with it. But, I wanted another .45 for some reason.
I went with an HK 45C and really like it a lot. I shot it all summer in IDPA. It carries well, draws well, is consistently accurate, and has less felt recoil than the 1911 with the same load. Initially, I thought: 1) I might not like the polymer frame; and 2) I might not like the DA/SA trigger pull.
But now after hundreds of rounds, the trigger pull seems natural, and the light frame combined with the recoil system it has makes the recoil seem a little lighter than the 1911 and very manageable, even though it is smaller and lighter.
Dislikes of the HK would be: 1) I felt the grip surface of the polymer frame by itself was a little slippery feeling and I wanted a very assertive grip, even when wet, so I added a Houge Handall; 2) the magazines are difficult to load easily and quickly unless a Maglula is used.
I would HIGHLY recommend the HK 45C.
Lou