About half of my library is PDF (don't ask, lol), and the Sony 950 is now my device of choice for those. The price tag is steep, but it's worth it imho. I found one for $200 at Best Buy, but if it broke tomorrow (and if I lost my extended warranty, ha), I'd rebuy from Sony for $300.
I'm getting WAY too much heat for pimping the Sony 950 for PDFs on the B&N forum, so I'll just say PM me if you'd like to talk more.
(Although my personal feelings are that if I pay for a device, I can gripe about its shortcomings all I want.
)