Folding bikes?

[schroeder]

I'm considering buying a fold up bike as some git stole my trusty old mountain bike from my back yard last week.
Are they any good to actually ride? The wheels all look so small. I mostly ride in the town, but sometimes ride on some more rough tracks.
thanks for your help in advance.

I have a brompton which is pretty good on roads and made up cycle paths but I wouldn't take it off road/ onto a mud path. I don't think it would run very well.

Thankyou for that azazello.
Hmm My problem is storage-we have a cellar with plenty of room,but it's extremely awkward to bring a bike up the narrow,steep stairs. So I ended up frequently leaving it unsecured in the back yard.
Maybe it would be better to install some sort of post in the back yard to lock a bike to?

It will rust badly in back garden, though, unless you buy a decent bike cover.