Polysphere vs LA

[asm74]

Are there any benefits to the polysphere 318 over the LA 318 engine designs? Is there greater power/efficiency potential in the polysphere head design?

I ask because I'm seeing a number of polysphere engines from ~1966 for sale.
 

[HP2]

The head may be viewed as somewhat more efficient since it is a pent head design, much like a chevy big block. However, as a pacakge they are less desireable because they are large and heavy for their available displacement and there is virtually no aftermarket support for them to realize any greater potential than street cruiser.

[71chally416]

If you want to be acurate, the BB Chevy is like the Poly, not the other way around. They originated in the mid 50's. 

Many of the generic small block parts will bolt to the old Poly 318, and you can even use the stroker cranks in them. The limitation comes in Intake and cam selection. TTI even now makes a nice header for them.
They have a Hemi type Intake port and a wedge type exhaust port so their is potential with some porting. Not as easy to build as the modern small block with all the parts available for them, but potential. There are some sites for them if you Goggle it.