I very much like the FL horses and as I said in my British Light Dragoon review, I think they offer the best level of painting, sculpting and attention to the detail of equine anatomy and movement available at this scale. That said, my answer to the question posed is "the one they have yet to produce." Admittedly I am a picky b*****d when it comes to horses but as good as they are, I have yet to see the combination of treatment of head, mouth and leg position that would qualify as my number one. Of course, FL has come the closest yet and the slight reservations I note are no better done, and often less so, by even the connissiuer producers like AeroArt. Moreover, these are issues quite often overlooked by many painters and sculptors, especially those doing military scenes. Very few of such artists commit the time and effort necessary to properly master equine behavior and motion.
The above notwithstanding, I have many favorite FL horses that rate my number two category and none from anyone else above them at number one. I especially like the carrage and positions of Uxbridge's horse although I would prefer a cantering version with a straight neck. I also quite like the Light Dragoon officer horse but would change the hind leg placement, close the mouth and remove the tilt of the head. The tilt is not wrong, just overdone I think. Of course as noted in my review, I also think the tail cut is overdone, even by historical standards. There is much support to indicate that on campaign, British cavalry horse tails were allowed to grow somewhat longer and that the standard cut (called "nagging") was longer than shown. Contrary to popular misconception, "docking" or cutting the bone to shorten the tail, was abandoned by the British cavalry before the Napoleonic wars but persisted in practice longer by certain dim witted civilians. The dock or tail bone of a horse is about 12 to 18 inches and the extreme cuts, as shown for the LDs did sometimes reduce the tail hair to that length.
Overall, I do love the FL horses, especially relative to others in this scale and I very much look forward to seeing one that will qualify as my number one. I have no doubt they can and will do it and when they do I hope it is a big bay in motion for a cavalry I collect. Until then, my number twos are quite nice indeed.