As an avid Worms: Armageddon (on the N64) fan, I can say that this is much more of the Worms that I love, just with more content, which is always a plus. Although it feels a bit slower than Armageddon, it makes up for it with new weapons that are very fun to use and strategize with.
Making custom maps and custom heads is also great and even for someone who doesn't play online often, I find myself making custom maps often just to see what kind of crazy stuff will happen this time. The customization makes for a unique experience every game.
If you consider getting a Worms game, get W.M.D. It expands on everything that made the originals good, and it's also NOT Worms Rumble.