Mapbox together with Digital Globe made it possible to have nearly full Satellite Imagery coverage of Thailand.
You might have to refresh the list of imagery providers in the JOSM settings dialog.
As tiles are limited to zoom 17 I did edit the config to limit to z17 (replace  by ) This enables “overzoom” which makes editing a bit easier.
Be extra cautious of the imagery adjustment. I checked in the Hua Hin area and it’s shifted by apx. 25 meters there. Refrain from large geometry adjustments if you are not certain about exact position. Better refrain from drawing building outlines when not certain that the alignment in the area you plan to work on is right (or adjusted).
Chiang Mai near the moat looks good.
Some areas have only black/white imagery which looks even worse aligned, compare Hua Hin Airport.
I have no idea about the age of the material. Some zoom levels still show Bangkok flooded. When zooming in further it’s without the flooding.
I am not sure whether that imagery is older or newer. Does anyone knows whether Don Muang golf course is still there? Imagery there is the same than used by google just, two zoom levels less.
After all that critics I think we can still be very thankful for that imagery which fills a lot of gaps in the Bing imagery.
I would be pleased to see if we can have the major highway network completed in this year. At least routable geometry.