I'd like to get some strap locks for my two new basses and would like some suggestions as to the pros and cons of the kinds available. Schaller, Fender, Dunlop? Are the Schaller and Fender the same? Do they all require new screws? I don't want to screw anything up with new fasteners. For the record I have a 1972 Fender Musicmaster and a Ibanez SR900. Thanks in advance.