I just switched to the Google Nexus and been very happy. I had an OV and was looking to upgrade on VM but decided to switch because of how slow my data speeds were. I personally went with T-Mobile and, while I haven't noticed any difference in coverage (living in a large metro area), my speeds have gone from an average of maybe 250kbps to 5mbps.
The Google Galaxy Nexus seems to work well, no real problems with the radio (the Verizon version of the phone seems to be having radio problems, but that is a CDMA rather than a GSM phone). WiFi is working quite well, with similar speeds to my desktop computer and far faster than the OV (OV only had 802.11b/g speeds, Nexus has 802.11b/g/n/a. Not to mention, having the Google version you are one of the first updated with the new versions of Android.
I'd recommend researching what carriers in your area are the best. This PC mag
study of the fastest data is a place to start, also the app Carrier Coverage, and check with people who live around you and that you work with how the coverage is on their phones.
T-Mobile has a $30 "Walmart plan" with 100 talk minutes and unlimited text and data (throttled after 5GB); though T-Mobile can be spotty so check coverage in your area. Straight Talk (using an AT&T Sim card) has a $45 unlimited plan, though they appear to throttle after 2GB/month or 200MB/day and allegedly have cancelled the subscriptions of those that use too much data. But the Straight Talk advantage is that AT&T has a wide coverage area. There may be others carriers, in your area, that are worth considering. And it is a nice advantage having the choice of carriers and, if you find a better plan, being able to change your provider by merely swapping the Sim card.
I have no regrets about making the swap.