PerroneFord
Deals in Lead
A higher bitrate can certainly yield better quality (with either H264 or MPEG-2 compression), but to get notably better quality than AVCCAM or XDCAM EX (at 35Mbps) takes considerably higher bitrates (diminishing returns). For some purposes it makes sense to use a nanoflash, but the resulting files are much bigger.
As XDCam approaches the bit rate (and file size) of what's getting recorded to P2, it's issues disappear. And I haven't heard to much complaint about the file sizes of DVCProHD.
But yes, AVCHD is always going to be more efficient. And Wavelet is even more efficient than AVC encoding which is why RedRAW and Cineform and MJ2K make such compelling formats. And they are easier to decompress and edit than AVC as well.