I have a Pedersoli double in .50 cal.
I had a devil of a time developing a load that it shoots well, but I finally came up with the answer.
It doesn't shoot round balls, common BP sabots or common BP conicals to anywhere close to the same point of impact. Yes, I could have used one of the two sights for each barrel, but that, in part defeats the purpose of a double rifle, at least to my way of thinking, because the second barrel wouldn't be instantly available.
Testing showed that this rifle had the characteristic property of regulating a double: bullet weight is critical. My rifle prefers bullets of 450 grains, and despite the listed twist of 1:48 shoots them well (actual twist appears to be 1: 39.4). Trouble is that there isn't a readily available m/l bullet of this weight available in my area. So I purchased Lyman mould # 515141, listes at 425 grains, nominal, with #2 alloy. It throws bullets alloyed from 1:160 at 451 grains, and produces very consistent bullets. The problems were, unfortunately, not solved in entirety at this point. The bullets were very difficult to load as they were about 0.515" in diameter, and the rifle has groove diameters of 0.5119 and 0.5121". OK, I built a swage to reduce bullet band diameter to 0.5120", and reduce the base diameter to 0.4980" (0.0005" below bore diameter for these tubes) for ease in loading, and decided to add a hollow point to the bullet while I was at it. The bullet was markedly easier to seat, but still too hard to load for a practical field rifle. So I ended up building a second swage to produce rifling grooves on the bullet, these are just 0.001" wider than the corresponding grooves of the barrel.
The second swage did the trick. The successful load is 80 grains of GOEX ffg, topped by a felt wad follwed by a pasteboard wad then the bullet. This combination is easy to load and accurate. It is capable of shooting grapefruit sized groups at 100 yards (off the bench), all that I feel that I should be able to do with my aging eyes.
The sights? Oh yes, I replaced the blade in one of the factory sights with an express type blade I made. Why? I didn't like having my view obscured by what is in effect, if not intention, a buckhorn rear sight. I simply don't use the other sight.
If you like a challange, you may like a Pedersoli. On the other hand, your rifle may shoot some sort of standard bullet well right out of the box.
Bob
I figure the Kodiak might be a good way to get into double rifle shooting. I'm looking specifically into the .72 caliber model. 
lol
