Welcome to our forum.
I will say that I’m a D1 dealer and have taken two D1’s in trade in the last year (an early 80's model and a 1993 Chairman) but have at least 8 Sundance out back ranging from 1989 to 1999. We repaired and resold both D1's but haven't been able to get to Sundances up to working order to resell. Saying that I have to add that they have done a whole lot to improve the product in the last couple of years.
This comment kinda annoys me. You sell D1 so it would make sense to a consumer that you would sell the D1's faster than the Sundances. Don't we always say buy from your local dealer. You obviously are not the Sundance local dealer. That is probably why you haven't sold the spas that are outside. We all know the Sundance product is a superior product.
I don't think this is a pissing match that you want to get into!
Purely from a consumers perspective and considering only the 2003-2005 lines, I would agree that Sundance is a superior product to D1. I have no knowledge of past performance or history. Just based upon my own observations and what I have learned from researching for my own information. (Now was that about as useless as a post can be? But hey like someone pointed out it's monday and I'm just glad we aren't bashing Master spas! )