Although the manga is better than the anime... go ahead and watch it. It will keep you very entertained... specially the last episode of season 1.
PS: If you really are going to watch it, then watch the uncensored version!
Don't listen to all these manga purists. The anime is good, ofc the manga is WAY better but there is no reason for you not to give it a try. It has some very cool fights. Just once you finish watching it, read the manga as well.
Yes, definitely. The anime is pretty good, but as said above, it leaves out things that were in the manga. Watch both seasons, then pick up the manga from around the point the anime left off. You'll notice the difference quite quickly.