Anything is better than nothing.
We've talked about the usefulness/uselessness of Agile around the water cooler many a time and we generally agree that what matters is not the process itself, but that you HAVE a process. It doesn't really matter what it is, so long as you have it, you document it, and you follow it. (And you improve it whenever you find flaws.) Do that and your Agile process or Waterfall process or even Donkey-Unicorn Rainbow Fart Party process will be better than NO process. (Or any poorly defined process.) Switching to a completely different process only improves things if you do a better job of documenting and following than you did with the last process, and is not a function of the methodology itself.