what is the best small block and why ?

Dang you got your 340 Dirt Cheap.
Yeah, it was complete when I got it. Also the guy I got it from was a BB person he had a 572 Hemi sitting on a stand (ready for install into a 68 Road Runner), a 440 6pak sitting in a 71 Cuda (guy was really cool and let drive the car around his huge drive way).