I doubt you will find too many people with hands-on experience that can provide the info you expect. It will most likely simply come down to this: Buy whatever gives you the best bang for the buck today. It's inevitable that there will be a newer/ better processor out there tomorrow/ next week/ next month/ in half a year. For Adobe software it will be mostly irrelevant, anyway. Even if you got an 18 core Bulldozer chip, AE's multiprocessing limitations would still prevent you from exploiting its full potential...
You would not want to go AMD for the CPU: Even with the Bulldozer architecture, the "eight-core" AMD CPUs are still slower than quad-core Intel CPUs (yes, slower than even i5s) when it comes to performance in Premiere Pro CS6. This is because although the FX series CPUs support the full SSE 4.x instruction set, the SSE unit in those CPUs is weak. And forget about the Athlon and Phenom series CPUs at this point since those CPUs lack full support for the SSE 4.x instruction set.
For proof of the AMD versus Intel situation look at our Premiere Pro BenchMark (PPBM5) database. If you click on the column heading "Brand CPU" you will get all the AMD CPU's test results. Then look at the first column and you see the ranking out of the 1169 results (today's total) and as you page down you will see that the best AMD score is indeed a 8-core 8150 FX but it is ranked 465th out the 1169 results.
My several year old i7-2600K Sandy Bridge quad-core is much, much faster than the 8150 FX. There is no reason why you should have to pay $700 more to beat the 8150FX.