I have had Titan early and moved to Mammoth, using Thunder all the way. Both are similar, but I now have Mammoth M2 at the highest Mu, basically M3. With M3 Thunder I almost feel bad taking out the lighter hulls. (almost) I enjoy going for the flag and trying to return our flag. Even if I fail I do a mess of damage on the way. If I am being healed it takes 3 or 4 enemy tanks to take me out. I will continue with Mammoth.