I have heard mixed reviews about them with respect to staying in place and not shifting under heavy recoil. That may have something to do with the attention to detail of the person installing the mount as opposed to the mount itself but your mileage may vary.
If you are going to D&T the top strap you have lots of choices.
Both of these seem to be popular and generally of very good quality. I own products form both companies and have been 100% satisfied with both.
If you don't have the gun already then I would recommend that you take a look at the hunter model of the SBH. It has integral scope mounts and will not require any extra work to get your scope mounted.
I have successfully used the Weaver on several SA's. However I did split the ring that encircles the top half of the barrel ...excessive recoil?
Maybe as my pen name is Dr Loudenboomer