Plus, you'll get a good set of adjustable dumbells and plenty of spare weight which will last you forever for roughly the same price. On bullworkers, the bands wear out after a while and so they need constant replacing.
Also, free weights, particularly dumbells enable you to work your whole body and not just your chest and arms, as well as ironing out imbalances.
If you want to look really gay and stupid by just working your chest, do pressups which are free and don't cost you £75.