Well, I have found that TS's palette is really difficult to operate. Getting a gradient between two colors requires one to search the palette for that one pixel, and click it the right number of times. The lack of rotation tools is also pretty annoying. I think the only ways that TS has the GameDev editor beat is in the random fill tool and being able to see how a tile looks in a group. Though neither have the option to edit two adjacent tiles at once, which would make backgrounds alot easier...