I've got a very basic tern, the equivalent of that dahon you had. It is good but the clamps needs constant adjustment to keep it tight. It's a strange system whereby you screw a connected bar to increase the tension in the clamp. There is loctite on there but it doesn't seem to do a lot and if i'm honest i have been slack in getting some more to douse the tension bars in. You also have to grease the contact points up a bit otherwise they creak when you ride. Based on the brompton i hired and the tern i own, the brompton clamp system is far better but the tern is a much better ride, clamp foibles aside. Like you i don't need a super small fold as its just to go in the back of the car.
Oh and whilst i'm moaning, the fold system is a bit daft as the bike is held in two by a poxy little magnet system which is on front and rear wheels. Fine if you pick it up by the side that swings open as you can sort of brace it against your leg but if you grab it the other way round it has a tendency to swing open. I think people that use them on trains etc just carry a short bungee which is abit of a bodge.
If you're still looking at tern and don't need a small fold then they do one which is a slightly bigger wheel again, the eclipse X20 from memory which might be worth a look.
Also, if it is a concern i would imagine the residual on the brommie will be far better.