What is best GPS for Yunnan, Sichuan and Tibet?

Can you give me some impressions of the best bike GPS to use in China?
I travel to the US twice a year and can buy stuff there.
I'm not sure which system is best for the hinterlands.... When you get on the backroads of northwest Yunnan.
Anyone who has experience going north of Shangrila or up the Nujiang River past Gongshan in Yunnan? There is only one main road but there are a lot of out of the way places in this area I would like to explore and I am interested in getting advice from anyone who has used a GPS in these areas.

I don't read Hanzi so having an English GPS is important.
I suppose I could use the Chinese version as the roads are numbered. It might get dicey in the small, remote roads but then even having a Chinese road map would be useful.

Any experienced adventure riders living in Yunnan interested in visiting these places please contact me. I'm not interested in large groups. Maximum 3 or 4 total riders.

Thanks
Rob