I agree with the bed... I went from a $300 Queen size I got from a mom and pop store... to a Serta King also (I think its the same one as Darkstarrs) the difference is night and day. I will never go back to a cheap bed unless I absolutely had to.
My glasses... I have 2-3 pairs of glasses, each were $500-$600... The way I see it, well I'm gonna be wearing these things everywhere, I need them to be comfortable as well as durable. I try to find decent frames, but I always go for the best lenses.