Hi
Ive done quite a few urban searches too with MR, the forces issue gaiter are a good choice and durable.
Another option is too wear wellies which are better for some of the ground you might be covering particulary old industrial areas and rough ground.
Some of my collegues wear overalls and a heavy duty PVC suit if conditions dictate, certainly saves wrecking your expensive Gore-Tex and decent boots. Ed
I have worn wellies in the past - and they are good for stopping thorns, but I was ticked off about it. Apparently we aren't allowed to wear them because they don't provide adequate ankle support, which means that it's generally a case of what will fit with hiking boots.