One of our usual 'go to' sites.. www.videohelp.com has almost no suggestions for converting/burning MTV or AVCHD files to any other format let alone DVD's. And as you've probably found out doing google searches pretty much everything that comes up is a pay-for program that may or may not have a trial.

I'll let others weigh in if they can but if you need to go to a program that costs money the only one that I found doing searches that I'd have some confidence in would be Boilsoft's video converter.

http://www.boilsoft.com/dvdcreator/mts-to-dvd.html

http://www.boilsoft.com/avchdconverter/index.html

I only say that because I've used their software for other purposes and it's always seemed to work well. From what I've seen from legit software download sites like www.tucows.com there's a 30 day trial for that program so it might be worth a try.

http://tucows.com/preview/736454/Boi...ter?q=boilsoft

As for speed, well any type of conversion and/or burning can take quite some time esp on a laptop or older PC so I can't say that this or pretty much any other program will do a particularly speedy job... esp if the file(s) are of any significant length.