Ive used the Nissan ones for a bit then quit, stainless, but plastic inside. The first one I got lasted a long time I really loved it, it would keep the coffee HOT pretty much the entire day. THen it let the vaccuum out and didn't work. I got another a few others two years later. They didn't do nearly as well as that original one did and actually only lasted a few months, I was very disappointed. I got ONE more just to make sure I just didn't get a lemon batch. Same thing, it didn't do nearly as good a job as keeping the coffee hot. Then I heard liquid sloshing around in it between the outer and inner 'cups'. Ok so now it has a leak. Put it into my SS recycle batch and never used a nissan again. For 20 bucks for a @#$ing coffee cup you'd think it would last longer than that.... sigh...
Aaron