I've been using a MyPillow for around 2 years now. I think it's a good pillow and I like it, but I wouldn't describe it using all the superlatives the guy selling it does. IMHO the sale price was a fair price - MSRP was/is too high.
I also have a MyPillow mattress topper. Bought it at Kohl's over a year ago where I got the pleasant surprise that it was marked down 90% (!) as an unadvertised "closeoout" and had some coupons besides so it was really cheap. It's comfortable and I like it.