What are the stats on your wheelchairmotors? The ones I handled in the past were rated up to 400W, on 24V that means less than 20 amps. (mobility scooters are another matter, and can go as high as 1kw on the single motor that drives the dif)
Even if we stick to the rule of the tumb that a brushed motor does 4 times nominal current in stall it won't blow the TZ85's.

But if you want to be sure, go for the Wotty. Then you support a roboteer. Buy British manufacture and have super fast and accurate repair work if needed. And it's made for our purpose...