Dudes,
Sorry to contradict, but these aren't the same Hoshino as the Tama family Hoshino Gakki. I wish I could give full details, but I clearly remember this from a late 70s International Musician & Recording World review of them. They explained that while both companies had similar names, the Hoshino set reviewed was not related. The first drum pictured resembles Tamco drums, a mid-80s Superstar look-alike.
As I recall they weren't especially exciting, the one distinctive feature I can remember was that the toms had more lugs than usual. The 13" tom for example had 8 lugs, as shown in the pic of dno's set.
BTW, this review was from '77 or '78, at which time Tama had already been in full swing for 4 or 5 years under their new name.