Suse is really robust.i loved it when i used it.But sience novel got it and meses around to get$$$ i switched to Ubuntu and i love it even more.
I say if you like to pay for support you wil get one by using suse.It is real robust gui oriented .
If you like to figure out how things are done by reserching posts and support from comunity ubuntu is here to stay at no charge and its suport from comunity is really wide and growing.
redhat -no thank you.
I would say if you are any closer to use the OS on the Enterprise levalelthen nothing better than global leader in Linux Red Hat. It gives excellent and speedy updates with quality support. Just sit and work with free mind.