I honestly would not buy a computer that wasn't Ant+ compatable. Just in case you ever decide to get a power meter, you'll already have a HRM and computer that works with it.

The Garmin 500 is what all the Garmin sponsored teams will be using this year I believe, $350 for the bundle with the heart rate monitor.

Bontrager is also coming out with their node series which fairly reasonably priced.

I use a cateye micro wireless, no HRM though.