I use premiere pro and it reads avchd files ok but the playback on the editor is really juttery and no where near smooth, to get smooth playback and easier editing you need a pc with huge processing power (8gb ram +), which is added expense. My opinion would be avoid avchd cameras if you dont want to waste countless hours of failed editing, i would love to hear from people who havent encountered these problems.
I have a HF S100 from Canon which shoots AVCHD. I have had no problems with Adobe Premiere CS5. I'm recording at the highest data rate allowed for my camera 1080p 24 Mbs. Although I do have a beefy PC. 12 gigs DDR3 intel i7 930. ATI radeon 5790.
But one thing you should look into if your having a hard time is "raid" or setting up a "scratch drive"
Look them up if you don't know what they are.
and dont even get me started on them ski people riding in the stunt ditch. that shit is wack yo!
I've had this problem today actually filming in AVCHD format with my new Canon EOS 550D. I think if you're using Adobe Premiere Pro, you need to have CS4 or above for it to be able to process AVCHD smoothly.