The Sport band is difficult to come undone, but I've had it happen once while moving luggage. It happened when a strap pulled sideways on the "tongue" and it only stayed on with the peg.
I'd say that the new Sport Loop looks like a good pick since the free end won't slide out of the lug slot (much like the Milanese mesh loop). Even if the Velcro comes loose (unlikely), the strap as a whole stays connected.
Or there's the Link bracelet, or any similar bracelet. Steel bracelets used to be the default for sports & dive watches before durable rubber straps were invented.
The regular nylon strap with the buckle should be fine, too.