I think they are great in the 375 H&H, I tried to buy a bunch years ago and they were always sold out. But I'd load them for plains game in a heartbeat.
I've said it before and I'll say it again, I have used them for years in my 375, on many hunts, on all plains game up to Eland and on big cats. Hand loaded right, and with correct shot placement, you will have no problems. The 250gr SGK's are good, accurate bullets.