I agree with Racedog. I gave up my Nexus for a similar reason. I absolutely LOVED the phone - it was awesome, screen was nice, the phone was fast, the camera was speedy, etc., etc. I did have a couple of mic and in-call issues that pushed me away. If I didn't have those issues, I would have stuck with it and wouldn't have considered anything else, but those issues were there and I couldn't live with it. Plus I'm someone that refuses to root and rom. I don't have much time for it, and I would like something that works like it should straight out of the box. To me, a phone needs to be a phone first, and a computer second, so I went with a 4S.
I still kind of lust after the Rezound and the Maxx, as I think they will suit me better than the Nexus, but each has something that I don't like (all bloat aside). The Rezound has a pretty weak battery and the Maxx's camera is slow as molasses (I had a Razr for a bit too so I've been down that road before).
For me, the 4S at this time is something that fits me. It's a phone first, and has good battery life and a great camera. Those were what are important to me, and may not necessarily be what is important to you. You need to find what is important to you in a phone. If you're having issues with your Nexus and your Rezound worked fine and didn't have those same issues, I'd consider switching it out, especially if you're not someone who likes to root and rom.
But again, it's all about what's important to you.