Best Infrared/Full Spectrum Sauna?

I have a portable Therasage sauna that I got last year. I am not a huge fan of it, since it has foam, plastic and other materials I think may off-gas, even though I spoke with the owner and he said it does not, they conducted lab tests...I am still skeptical. I am looking at Sunlighten and Finnleo saunas. I am pretty broke right now, even though I'm working. My money goes down the drain- mostly with treatment and seeing doctors- a story you all know too well.

Does anyone have a sunlighten sauna or other really good far infrared or full spectrum sauna they can recommend?

I use High Tech Health (http://www.hightechhealth.com/products/thermal-life-saunas). Have had it for nearly 15 years I think. Still works great. It's expensive though back then it wasn't.