I think I can claim some familiarity with the Bounty; I did a great deal of reading about her some years ago when I was working on my little model of her. From the standpoint of scale accuracy the only Bounty kit I can recommend is the one from Calder. The people who operate that company know how to do research; they obviously looked at the original Admiralty draughts of the ship. (The first clue: the captain's water closet at the stern.) Mamoli, Sergal, and their ilk are what I call the HECEPOB - Hideously Expensive Continental European Plank-On-Bulkhead - manufacturers. (Hey, if other people can make up words, like "TallShip," so can I.) Those manufacturers are notorious among serious scale modelers for producing kits based on inferior materials, irrational construction methods, unworkable plans and instructions, and non-existent research. (If that seems harsh, check out this link: http://www.naut-res-guild.org/piracy2.htm
It is, of course, dangerous to generalize; I don't pay much attention to HECEPOB kits, and I'm sure they vary a good deal in quality. But on the basis of what I've seen I can't recommend any of them. One partial exception to the rule seems to be Amati, which has just started issuing a series of British warship kits under the label "Victory Models." These kits, as I understand it, are designed by an extremely competent Englishman who used to be affiliated with Calder. I haven't seen any Victory Models kits firsthand, but on the basis of photographs they look excellent.There are four other wood ship model kit companies whose products I can recommend: Calder/Jotika, which is British, and three American firms, Model Shipways, A.J. Fisher, and Bluejacket. Those companies' products do vary in quality somewhat (as is inevitable), but the people who run them know what scale modeling is about. I've wondered more than once whether the people in charge of the HECEPOB firms have any idea of what a scale model is.
Regarding that Sergal "Presidential" - I haven't seen a kit with the Sergal label on it in a long time. I understand, though, that most of that company's kits are now being marketed by another Italian firm, Mantua. The Model Expo website includes a picture of a Mantua kit labeled "President;" I wonder if that's the kit in question. I'm not at all convinced that any such ship ever existed. The invention of ships out of thin air is a favorite HECEPOB stunt. The models in question usually turn out to be based on recycled parts from other kits. In this particular case the description in the ad is suspiciously generic, and the model in the picture is something of a mess - especially with regard to the rigging and the flags, which are totally wrong for the time period claimed in the caption. And the hull shape looks remarkably like that of the Bounty.
I've typed more than one rant of this sort in this Forum, and I always feel a little guilty about them. I know lots of people get lots of pleasure from HECEPOB kits, and it's certainly not for me to tell those people not to buy them. But I do tend to get upset when these companies claim their products are scale models - which they most emphatically are not. To call them scale models constitutes deceptive advertising at the expense of innocent hobbyists, and I think purchasers are entitled to go into such expensive transactions with their eyes open.