Verizon Message+ is by far the best messaging app. Take it from someone who has tested every major SMS app in the market. While users complain about Verizon and RCS, Message+ is already chat capable amongst all Message+ users (including users with other carriers, something that RCS cannot do)
My only gripe is that the app should be updated more constantly. We've been sitting on version 6.6.7 for a while now. The app's functionality is almost flawless, but it could use a lot of improving in the cosmetics department. If you use a custom background it just looks ugly and the text is almost impossible to read, plus the depressing gray top bar that it's impossible to change when you have custom backgrounds. A more simplistic design like iMessage or Android Messages would help a lot.
Message+ may have a few RCS like features but it's still proprietary. The real win for all Android users across all carriers is RCS Universal Profile. As of December we are finally on our way to industry standards for replacing SMS. Verizon is slow, granted, but RCS should now work well with Google's support.