I run an AT1KM Palstar, however not full legal limit.
From my elmers, if you truly run legal limit, look at the roller inductor tuners rated at 3kW. Though mine is rated at 1200W, it's not really the truth, it's really for a 3-600W range amp like an 811H.
Also for full legal limit, actually any tuner, run cleaner through them to prevent arcing. If you have pets, smoke, etc, check them out and clean them up two or three times a year to keep things happy inside. Not cleaning tuners is the primary cause of arcing over and generally blowing them up.