I don't know what to get i heard the new 44's are good but do i want to go with the original 40's, some please help with some tech.

The 44's are the most aggressive muffler that flowmaster has. The 40's aren't far behind and are a good choice either way, I think they will sound good.

I had the American Thunder Kit on my 06GT but my old ears and nerves got tired of them. I removed them and have them in storage and put my OEM mufflers back on with my headers and off road X-pipe and it sounds great to me. The American Thunder set has the original 40 series mufflers, I think, and the chrome 4" tips. I'd let them go fairly reasonably, I think about $200.00 plus shipping. I'll post some pictures as soon as I get a camera.

Neither. Mac Flowpath all the way.

I have purchansed a Mac Prochamber already, i have not installed yet, i am awaiting picking out mufflers, why the Mac Flowpath?

Because they sound way better than Flowmaster. Coupled with a Prochamber, you'll have a real nice low rumbling idle and a rip snorting roar at WOT. If you're not looking for something obnoxiously loud, it's not the setup you want though.

You got the Mac Prochamber already, so mine as well go with the flowpaths Either one will do and you can't really go wrong.

I say 40s always sounds good

okay so i've done some research, i'm going with the Mac Flowpath but holly cow they are expensive i found some with part # TK2546 they are stainless with 4" rolled angle cut tips but the price is like $349, does anyone know, were i can go or how i can go about getting this setup for cheaper, i haven't had time to check out ebay yet, and i haven't found anything on craigs list.

also will it hurt to install the prochamber and the put the mufflers on in about a month?