It kind of depends on your horse's shape and sensitivity. If you find a cheaper one that suits your horse's girth area he could be a lot happier than with a high end girth that doesn't fit his anatomical shape. You also need to consider how often you would like to clean your tack, especially before buying a lambskin or leather girth.
Nowadays the top seller girths are the neoprene ones (it doesn't matter the brand).
As Erica says, Wintec has really good value ones, I use one on my dressage saddle and I'm really happy with it! ☺️
Yes, fairfax is one of my personal favorites because it allows more movement in the horses shoulders. Now if your doing lower dressage levels it's not a big deal, Wintec happens to make a few really nice low budget ones and they're super easy to keep clean.