I'm not permitted to bind, myself, but going by reviews the strapless binder is really great and velcro binders in general are awesome. When I finally manage to get a binder, the strapless one is on my list.
Also, you might want to check out sohoeva-they're a brand new site that sells a strapless pullover binder for $15. Some people think they're a bit risky, but they're worth a try.