Is the German Reticle #1 by Leupold a good dangerous game reticle for a 1.75-6 variable mounted on a 375 H&H?

If not what is a good use for this reticle?

What would be the reticle of choice for the 375 H&H in that power range?

The German #1 was designed for quick target acquisition, and it does that well. It may be be bit more difficult to shoot tight groups with it at the usual 100 yards, but that's not what it was designed for. If you use your rifle for Buffalo and other large game at relatively short ranges, you're good to go. I usually use a 2.5x10 or 3x9 on a 375, but that's because I use a large bore for dangerous game, and the 375 for an all-around caliber in Africa and Alaska.

The #1 reticle was made for hunting in dim forests and night shooting without lights but is basically a very old tradition. I suspect the superior #4 was hard to make in the early days because of the difficulty of having hard metal posts and a thin wire or spider's-web crosshair in exactly the same focal plane without the latter being cut under recoil.

I have a heap of old German scopes with the #1 reticle and they vary in aspects such as whether the vertical post has a blunt picket or a sharp one (the point of the latter tends to get lost in poor light). They also vary in whether the point finishes centrally between the side bars or aligns with the top of them. I prefer the former because it helps when zeroing to shoot high at mid-ranges - the top of the sidebars can them represent the bullet strike at, say 150 yards.

As Beibs says, it does not lend itself to tack-holing groups, yet I managed a half-minute group when I put an old 2.5x Nickel on my father's 40-year-old Anschutz .22.

So, I think it is a good reticle for dangerous game and hunting in the extremes of daylight but no better than the modern #4, which makes more sense at long range and in FFP variable scopes.