If by Mercedes, you mean the A class - avoid that like the plague!! - the car is good enough, but the garage bills will crucify you as anything that needs to be done virtually results in a full car strip down to get at anything - and at Merc garage prices, this makes it a very bad buy.

The honda and Ford will do you well, with the ford being a cheaper bet. personally, I'd suggest you go with the Honda as it is a little more distinctive and you won't try unlocking the wrong car in a car park!! (only Joking)

You are probably best to drive both and see what feels better for you.

 Hope this helps