I tried one before reading your message and now wonder why I didn't try this sooner rather than be put off by all the negative stuff I have read on the internet about AVCHD. It was no different than Mpeg4 with a different camera, but the results were even better using AVCHD.
It it is tiny bit more trouble to move the file from the SD card to the Faststone Image Viewer to get it on my computer since the Canon Image Browser doesn't recognize it, but easily worked around by opening the SD card in Faststone and copying the file to Faststone.
I clicked on the drive (K) to open the SD card, clicked on Private, clicked on AVCHD, clicked on BDMV, clicked Stream. It was the latter I copied to Faststone.
I then loaded the file in the video editor, made a few adjjustments, and clicked on Produce. clicked on File, Using H.264/AVC I clicked on Advanced and changed the bitrate to 28000+ that i got from poperties and the frame to 29+. The actual original frame rate was 59, but 30 is the top option on the converter.
I am very pleased with the result and wondering why I didn't try one sooner.
If you see anything I should have done differently, please let me know.