The answer to your question is that double rifles aren't bolt rifles. Recoil-wise, they are what they are when they leave the maker, and recoil reduction "improvements" are usually offset by equal detriment.

With double rifles, it's all in the geometry, weight, and fit - all impact "felt" recoil. The greater the recoil, the more important good fit becomes. Stocks can be bent, wood removed where necessary, and recoil pads added or changed. Correct LOP is much more critical than with a light rifle. If recoil is a problem for you, engage a professional fitter and have your stocks altered accordingly. If your double rifle still kicks too hard for you, you got the wrong one. Sell it, and try again.

A modest difference in weight usually makes a dramatic difference in felt recoil. A 10 lb .470 can be unpleasant at the bench. A 10 3/4 lb .470 is much more pleasant to shoot, but it had better have been built to BE a 10 3/4 lb rifle, or it will swing like a Hoover. I've shot quite a few doubles with recoil reducers installed, and am absolutely convinced that they work solely by virtue of the added weight. If there is any other magic, it would take someone much more sensitive to recoil than I to discover it. The wonderful handling dynamics of a good quality double rifle are 80% of what a fine double rifle IS. Shoving a mercury reducer up it's ass murders it.

In today's market, the UGEX 9.3 Chapuis is the best bargain there is. They're really nice rifles for the money. However, they're usually within a couple ounces of 7 1/4 lbs, which is 1 1/2 lbs too light. So, yeah, it may sting a little from the bench, but it won't bother you in the field at all. Make sure LOP is right for you, add a good pad, and leave it alone.

A double rifle has two barrels, but it's still a rifle. Like any other, if you want to get the most from it, you must spend the time at the bench - there is no other way. If you can't handle it well from the bench, you probably won't handle it well in the field either.
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