Personaly, I use medium units. My vid card cant handle much more and still deliver a satisfying game experiance. The number of men in a unit and all the smoke effects and things cause an irritating slow down or it gets too choppy. I would love to have ultra size units in E/N:TW, it was awesome to have it that way playing Shogun, Med I & II for the "Braveheart" effect. Talking about it makes me want to drop cash on a new card lol.
Also as stated above, the AI does have some pathfinding issues with large units. IMO, its just a drop in the bucket compared with some of the other idocyncrancies(sp?), tics, and....frankly...retarded things the BAI does. Honestly the BAI in even the "BAI upgraded" Napoleon: TW, has yet to suprise me with its tactics, but that is a post/rant for another thread.
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