We purchased an 06 Avalon/Cal Spa new in 2007 (it is an 06 model)
Basic info: It's a 5 person-deep seat, 450 gal, full foam, with a waterfall, ozone, 2 filters, no foot volcano....we live in the Northwest. I only use spa chlorine, baking soda as needed, and Metal Gone at start up, in the water. Never had a foaming problem and clean the tub every 3 months. It's always sparkling and fresh. I'm particular about who and what goes into the tub. ;)
It was purchased and delivered by the local Cal Spa dealer. The delivery guys were rough around the edges but luckily we were knowledgable enough to have everything ready. We had prepared the pad, knew how far to place the tub from the electrical connections, water source, read up on chemicals, etc. A little knowledge in hot water chemistry and readying your space will go a long way! The delivery guys placed the spa, said, "fill it up and dump this in, then turn it on". I waited until they left and went through the start up. Metal remover, filtering and chlorine all to spec. Over the past 2 years and 3 months we've had no major problems with this spa.
Two smaller issues: One corner inner layer has delaminated and formed a bubble. We heated and re-seated the bubble (approx 2" by 3") on our own (something I wouldnt recomend unless you're familiar with the process) It was only in the top layer not affecting the tubs ability to hold water. We also had a small fitting under the tub get bumped by the drain hose and leak, an easy fix. We went to Cal Spa, picked up the part (brought them the old one for warranty) and they switched me out and we replaced it no problem. No need for a service call cost.
We've been very happy with this spa. ...again, basic spa knowledge before delivery will go a long way!