I agree with you that the tyvek suits are less than ideal, but they are a cheap alternative.
I prefer steam saunas simply because the steam heat produced combined with ozone produces OH radicals that easily penetrate the open pores of the skin. I know others have said that the IR saunas work well, but I would be concerned about the ozone interacting with the materials.Polyester breaks down very quickly with UV so why would it not decompose with ozone? Even PVC eventually becomes brittle when exposed to ozone.The sauna I prefer is made of a canvas material. At the risk of losing a lot of sales, I am going to post a link to the one I like on E-bay. It is currently selling for about $59.00. I've had one like it for eight years and its seen a LOT of use.