I did a little research a while back and concluded the following:

Don's a member here and builds a damn fine bumper - argueably equal to an ARB.

ARB also builds a fine product - argueably equal to or slightly better than an Don's.

ARB is twice the price.

ARB's already worth plenty of money.

Don does it for the love of the "breed" and can probably use the additional money.

If it were me, and it probably will be one day, I'd buy a Don's bumper.

87 Montero, bought new, by me -
88/89 intercooled Starion Turbo engine-
with awesome audio.