Yes, I now many of you are concerned about ASL's quality control issues. The quote below is taken direct from my website.
For those who have experienced quality and/or inconsistency issues with these units, you can be assured we have found the source of these problems and address them during the modification process. No more tubes going dead, biasing issues, open or shorted resistors, noise issues, grounding issues or circuit shorts. We have thoroughly gone through these units to find the source of any associated problems BEFORE proceeding with the upgrades. Your amplifiers will be returned to you in better than new condition and also feature our full 1 year parts and labor warranty. We stand behind everything we do.