I would do a savage, I have always wanted one, and there super strong

The other thing to keep in mind besides parts availability is the ability of the engine to hold a tune. Especially if you don't have much nitro experience.

Aside from buying a replacement O.S. for each, the Revo definately has the edge here. The Savage is not bad, not at the level of the 3.3 though. The Cen is a POS in the engine department. I don't have any experience with the new MGT 8.0, but generally the Super Tigre engines are good.

All of them will need a good clean up and seal up followed by a good break in.

i was worried about the CEN engines. but i figured theyd be ok.

maybe ill have to rethink that.

not sure