Verizon slowly but surely seems to roll out updates.
Unless you have an unlocked phone, your carrier determines if/when updates happen, right?
I don't use Verizon but friends who do tend to complain that they are often stuck waiting for updates. Even when the unbranded version of a handset has updates available, there is no easy way to install them on a Verizon phone due to locked bootloaders and such. If the VZW variant has different hardware, then even a standard factory image won't do you any good since they will be built for the "everyone else" version.
I really do feel for people whose only choice is Verizon. At least with AT&T you can usually just buy the standard hardware and pop in your SIM to avoid carrier obstructionism. With VZW, they really get you by the short hairs.
If you want/need a very good signal quality, buy one made of mainly of plastic instead of metal material; or an external antenna. The brand doesn't matter that much.