I've got a commercial built 27 ft trailer with the mh style axles but they are not mh axles. Lots of construction float trailers used 14.5 tires to keep the capacity high with the deck height low. The backing plates are bolted, they used the same bearings as 7000 lb axles etc. I've not put a lot of miles on the trailer but the axles have been fine so far.
My only complaint is those stiff tires are a mother to get seated. I've had one with a rachet strap on it all summer trying to get it shaped to seat. No luck yet.
Oh yeah, careful buying tires in 14.5, not all are DOT rated, some are mobile home tires, single use sort of deals. Not really any price difference but MH ones will get you a ticket in some states.