I've read the reviews of each kit individually though didn't see any that compared either AFVs and Academy's M-10 or M-36 kits. Anyone here have a definitive opinion on AFV's M-10 and M-36 vs. Academy's M-10 & M-36?

I won't comment on the M36s (although i've a sneaking suspicion the same comment applies) but certainly, in the case of the M10, the AFV Club kit wins hands-down. The finesse of detail, accuracy (although with a handful of issues) makes, IMO, the AFV Club one the winner...

Mike,

I'm a huge AFV fan and not a big fan of Academy but having said that, the Academy M36 is the better option from an accuracy standpoint.

AFV M36 @ Perth

Academy M36 @ Perth

Both companies M10 kits have received fairly positive reviews, however, I would personally go with the AFV no questions asked.

For the M-10, I'd go with the AFV Club M-10 duckbill, for the M-36 ditto, just change the engine deck. See the Perth review.
Basicaly the hull shapes and turret size are more accurate in the AFV Club than in the Academy one.

Sorry Marc,

but it's more than just the engine deck. The rear hull plate, exhaust and louvered deflectors, central hatch panel and a few other smaller nit picks as well.

Like you said, see the Perth review.

Which I did link to.

go for the AFV club offering, the detail is sharper, and the plastic is a bit better quality

malc.

The early M10's are a bit of a wash--the Academy turret is too narrow and the AFV Club turret too wide, so I guess it comes down to which bothers you more. AFV Club seems to have a better grasp of the general shapes of the M10/36 hull, but they didn't do the gasoline version, so you cannot build an accurate M36 out of the box. AFV Club's suspension is also chunkier with larger wheels than other kits. Reportedly the late "duckbill" M10 turrets are better done.
The Academy M36 kit includes more options including three gun tubes to choose from and an optional armored roof and optional postwar front plate with machine gun mount (apparently added for East Asian armies receiving US aid).
Steve Zaloga's book on Modelling US Tank Destroyers, published by Osprey, is a good resource on getting the most out of the available kits. It's available from Amazon.com.