Welp, got my DigiQ F1 in a trade from someone on the boards.. all I can say is that I've reserved comment until I put about a good 3hrs worth of playing time in.
I have the Toyota TF102. You can see pics in the DigiQ Gallery section.
Controller is awesome, I love the functionality and programmability. Carfeels a little cheap on the front end as Usagi reported, but it does seem to stand up well to abuse. I have physically put pressure on the front suspension in an attempt to break it (though I didn't use super human force

) and it seems to be able to take a decent amount of force before it feels like it's going to start to give. Fragile? Yeah, it is a little on the fragile side.
Playability: Whee! This sucker is fast. I got to play with it on a warehouse floor with several thousand square feet for fun. All I know is I -NEED- an IR booster now.

Once you hit a straight, this thing ZIPS real nice, turning was a bit too tight on the slick floor and I didn't have excellent traction, but I can see how the proper racing surface would do well. I tried my best to bottom out the car with sharp turns and such, but there isn't a single scrape on the bottom. I suggest sticking to flat surfaces for racing, no pebble-laden parking lots or anything.
Looks: Looks great! Excellent detail on such a small thing. I almost want to just put it up in a little case on my shelf!
Hackability; haven't tried to hack it yet. I think I may want to buy a single Car-ONLY to hack.. I'm wondering what a BCG custom conversion would be like using the dual battery/dual motor, and rigging up the front for real steering instead of just loose steering (just like a DigiQ).
All in all decent product, a little fragile. Probably worth about 45 USD (though I basically paid a bit more because I'm a sucker for these things).