The comments on the 45 are right on! Great plane and its fun to fly. I flew the 40/45 for several years and one trip to Europe--no problems. I think the early serial numbers had issues. Definately get the XR, although the regular 45 is no slouch. I think converting the newer pre XR 45s into an XR isn't that big of a deal. Don't know anything about the Excel, only that it looks bigger.