No personal experience, but I have read from someone (an older, picky gentlemen with alot of hunting/rifle experience) as I recall that was looking for a Leupold alternative due to zero retention problems... that the old steel tubed 1-3 Weavers made in El Paso, were the most reliable in his collection in regards to holding zero on hard kicking rifles. Not the best optically in alot of ways, but always trusty, small, light, etc. I think they had 3/4" tubes. For whatever that's worth.
Perhaps we could find one on eBay (and some 3/4" rings) and add it to the long list of requests for a Form drop test (haha).