There is no dual suspension bike in any supermarket that is worth buying. As a rule if it's under $1000 steer well clear and at $1000-$2000 it could be worth a look merely as an entry level bike. Quality dual suspension mountain bikes are too expensive and require too much after sales service to be worthwhile for a large supermarket retailer to bother with; they just don't move off the shelf fast enough. Dually's are finely tuned machines which require servicing and appropriate care to function properly - something only a good bike shop can do.