I have a Subal and the wife a Nexus; both for N90s cameras.
Here is the differences I've suun between the two:
The Nexus has slightly larger diameter O rings. Provides a better seal.
Subal changed O ring size several years ago and it can't be discerned just by eye. So if you are thinking about buying any used ports, don't get an old one mixed in as it will leak.
The Nexus is slightly smaller; better for small hands.
The Subal ports are a 1/4 turn bayonet lock as opposed to the Nexus which is a screw on. While we've never had a Nexus come loose, many times it takes two to unscrew the Nexus ports.
Both are well made and have a large selection of ports. Therefor there should be minimal price difference.
Be sure about your desire for glass over plastic ports. Plastic will scratch easier, but you can polish it out by hand. Push a glass port against coral and t will scratch also, but you can't polish it out.