I haven't actually built it, but I have one in my attic awaiting my attention. On the basis of close inspection I'm of the opinion that it's one of Heller's finest products, and one of the best plastic sailing ship kits ever. The "carved" details are superb, and it looks like (in contrast to so many of the company's other products) the designers worked from a good set of plans. I don't pretend to be an expert on French seventeenth-century galleys, but on the basis of the drawings and other models I've seen this kit looks like a genuine scale model.
It does, like any other kit, have some weaknesses that cry out for improvement. The biggest problem concerns the oars. The oars on the real ship were rather complicated structures, with heavy-duty wood parts to reinforce them where they passed through the hull sides and multi-piece wood handles attached to the looms. (Those oars were huge; a man's hand wouldn't pass all the way around the loom itself.) Heller molded each oar in one piece, and the result looks kind of crude compared to the rest of the kit. The handles and the reinforcing pieces wouldn't be difficult to make - once. Unfortunately, though, the ship has a huge number of oars (I don't recall the exact number). The repetition involved in fixing all of them could be pretty depressing.
The other obvious problems are endemic to the plastic sailing ship kit. Few serious scale modelers would find the vac-formed plastic "sails" acceptable. (A galley with furled sails, or no sails at all, wouldn't be bad looking.) And the flags, which form a big part of the finished model's spectacular appearance, are printed on heavy paper that's supposed to be folded over, doubling the already-too-great thickness. Again, making a new set of flags is normally no big deal - but in this case it would involve painting hundreds and hundreds of gold fleurs de lis on a bright red background. (I wonder if it would be practical to scan the kit flags and print them out on some lightweight paper. The gold ink wouldn't reproduce as gold, but that trick might at least be a start.)
Bottom line: I strongly recommend the kit, but with the reservation that realizing its full potential would require a great deal of time doing dull, rather precise, and extremely repetetive work. Frankly, that's a big reason why mine is still in the attic.
Youth, talent, hard work, and enthusiasm are no match for old age and treachery.