Looking at the reviews, Bosch ($59), DeWalt ($75), and Makita ($89) all seem to have their adherents.
Bosch seems to lead in smoothness and dust collection, but is slowest at removing stock and is more easily stalled if you press down too hard. (Ok, ok, "Let the sander do the work and don't force it!") Some have commented that they don't use it at any but the highest speed. I have a Bosch 1590EVS jigsaw I purchased gently-used on Ebay and really like it; it has secondary blade guides similar to Festool's to keep the blade straight. So I know Bosch made some good stuff.
DeWalt and Makita both are praised for their higher power. I have a little detail sander from Makita that does what it's supposed to, but I owned a DeWalt jigsaw for about 6 hours before I returned it because the blade kept falling out - a problem other people had with it, too. (A B&D drill I have works fine - made, of course, by the same parent company as DeWalt. BUT - I DID have trouble finding a replacement switch. As I did for a B&D router.) One Makita review was critical of the dust collection bag, but I figure I'll either be using it outside or using my shop vac to collect the dust.
Decisions, decisions . . .