I do not know that much about other codexes, but I quite like the Battlewagon. Sure, they are 110 points, but that is quite cheap for a super fast, av14 transport that can carry 20 people. Plus, it gets plenty of optional upgrades, like a s8 ap3 large blast killkannon. Also, if you use five of them in a blitz brigade formation, they get scout and always have s10 when ramming. Awesome.
Everybody always say that the dreadnought is really bad and that with av12 it instantly gets killed, yet every time I have fielded one (and I field them almost every game) I have always had great success with them. They stomp up the table, rip apart anything in their way, and sit on objectives while firing mass volleys of shots. I have only ever seen someone else field a dreadnought once.