What is the heaviest/longest bullet that will stabilize and perform well on game in a 1:12" twist 375 H&H?

380-gr. RHINO...?

Look at the link:
http://www.rhinobullets.co.za/

I thought that I had heard the rhinos had problems with stabilizing in game. Anyone have experience one way or the other?

Mr Geoff Mcdonald states that the 350grn should be the standard weight for big game with the 375H&H.
On preparing a friends Parker Hale Safari in 375 I was impressed how well the 350grn Woodleighs shot and performed.
ozhunter

I've shot the 350 and 380 grain Rhinos in my 375, but only at paper at this point. I'm having a tough time getting much velocity with French powders. Best I can get with the 350 grain Rhino bullet, over SP 11 (a spherical double-based powder) is 2310 fps, without compressing the load. I think this would do fine on large animals at bushveld distances, but it's not a versatile do everything load.