I have had two converters spec’ed and a 727 built by John. Last year I bought the DIY 904 kit. Both converters were spot on and the 727 lasted 50,000+ street miles and 1000+ passes. I had a question about the 904 band adjustment which he answered when I called him. I have heard that in the recent past he has had difficulty with staff. I know one 727 that was screwed from the beginning. I believe as we all get older it becomes difficult to keep up with the volume. Which is his stated reason for not building transmission’s and focusing on parts development. I personally have only had positive results with him. Sorry you had issues.