Not sure what width tires you are looking for, but if you are looking for a slightly wider tire than 1.5" the Geax Evolution II tires in 1.9" size have gotten very good reviews on the net. They have been referred to as "poor man's Schwalbes", in that they offer great durability and still roll fairly well. Schwalbe Marathon Plus tires ,while considered the best expedition level touring tires available, will run you close to $60 apiece. Geax Evolutions are supposed to offer very similar performance for about $30 each.