In my experience, AVCHD video is tougher to edit on Premiere Pro, although the updated version (4.1) is a much improvement. However, if you don’t mind tape-based cameras, the HV30 (or HV20) work very well. HDV is a less cpu-intensive codec than AVCHD.
I use both the Panasonic HMC150 and the HV30. With Panasonic’s free download of the MainConcept transcoder, you can convert AVCHD to SD or DVCPRO HD, so there’s a good work-around if you don’t like AVCHD (AVCHD still “studders” when you scrub it in the timeline of Premiere Pro CS4). See some videos about them at at HowNowVideo.com.