English Mastiffs' beautiful heads weigh more than the whole dogs of most breeds. Gustav and I took handling classes with a Mastiff named Ernie, who's head must have been bigger than a basketball. I'll never forget the first Mastiff that I ever saw. It was at my first dog show, and a big male was trying to sit in his owner's lap

If I ever switch to a short-hair breed, English Mastiffs will be my first choice.
I'm starting to see a few Tibetan Mastiffs at shows (OK, I've seen one

). They are a lot more Newf-like in appearance--big, thick coats, more proportionate heads . . . Neapolitan Mastiffs (think Hagrid's dog Fang in the movies) are fairly hideous in person. I was starting to like the breed based on photos, but seeing two champions in person was enough to put me right off the breed.
Bullmastiffs aren't even on my radar. Too small.
On a slightly different show-related topic, today I volunteered to be a steward at the local dog show this April

The Chief Ring Steward assured me that she'd do her best to have me at the same ring as the Newfs.