I don't sell the Buck Algonquin seacocks but they are probably pretty good.
There are a couple of features on the Groco that I like.
The handle can be set to close either to the right or left. The Buck will only close to the left. This makes the Groco easier to install in some situations.
The Groco also has a 3/8" square hole in the handle so that you can use a 3/8" socket ratchet or breaker bar to extend the handle if you need to.
The Groco is also drilled to fit the new Groco backer blocks which make installation
very easy and strong.
A quick search of the internet
showed me that the 3/4" Buck valves are about $15.00 cheaper than the Groco. I think Groco is worth the difference.
Groco Full-Flow Flanged Ball-Type Seacocks FBV750-2000
Groco Seacock Backing Block