Would you agree that these are two of the best...

I'm a fan of both, although I give the edge to Hoffman for his shapeshifting genius, particularly in the early years when he went from The Graduate to Midnight Cowboy and Little Big Man. His later career isn't as flashy, except Tootsie and Rainman, but taken in total his range was astounding.

Despite his excesses, or maybe even because of them, Pacino's work has always been exceptional. His character arc, alone, in the three Godfather movies would confirm him as one of the great actors of the late 20th Century. Whether dancing on a table top as the lethal/farcical Big Boy Caprice in Dick Tracy or as a doomed felon trying to go legit in Carlito's Way, he is never less than hypnotizing. He is also one of the few actors of his generation who, along with Hoffman on Broadway, has taken on Shakespeare. 

Like Rod Steiger and George C. Scott, he can go from subtle to blowing the roof off in a heartbeat, which has given him a reputation as a bombastic, one note actor among his detractors. But this is disproved by his work in Serpico and Insomnia. 

No. Great actors but no.

Yes, I agree, two of the best ever.

I agree about Tom Hanks, but that you don't think Dustin Hoffman and Al Pacino aren't great actors tells me you don't what great acting IS. What you describe is only ONE parameter by which to judge great acting, and a minor one at that.