Your chances of getting a flat in any given year are close to zero. What's worse is having something that fails when you're in BFE. Just get a breaker bar. Alternatively, HF sells a long handle, flex head 1/2" ratchet for about $20.I think the 12V socket fuse is a 20A. I'm really just looking to save time since I hate turning wheel bolts by hand. At $25, I figure the tool might be worth leaving in the trunk if it doesn't completely suck. On the other hand, I already own a Makita electric impact that I can just charge up and bring along for road trips.
Get a good pneumatic impact wrench for home.