This weekend, I went camping with two good friends who both have VZW Nexus phones (and, btw, I was highly jealous when those phones came out only a few months after I purchased the dreadful Droid 3). So, I got to do some comparisons in an area of very low signal strength (the valley floor in Yosemite park). I had pretty good signal in areas of the park, particularly down by the visitor's center. My friends, however, had almost no signal.
Now, obviously, this is a very limited comparison. It was just 3G signal in very compromised area and tells me nothing about LTE or signal in more typical situations. But, the differences in performance of my phone vs. the Nexus was marked.
In Los Angeles proper, where Verizon has an excellent network, the signal has been flawless and I virtually never drop down to 3G from LTE.
From hanging out with my pals and there Nexus phones around town, my impression is that they basically always have signal. However, they do seem to lose LTE access a lot.