Who should I buy a 727 or 904 from?

When I bought my push button BB 727 Dynamic transmission, I was given a full 1 year unconditional guarantee which was explained to me. They said, do what you want, drive it, race it and if it breaks we'll replace it. Here it is 2012 and never had a problem at any RPM and I been up in the 8000 range many times..