I love my mohair cinch, but I think it depends on what type of riding your doing. It takes them awhile to dry out and they need washed once in awhile. Versus the neoprene which is easier to clean and drying isn't an issue.
The only time I don't like my mohair is when we are on a weekend ride and the weather is humid. I have to put a wet cinch on the horse because it won't dry out from the day before.
That said, the mohair will stretch better giving the horse better respiration on a strenuous ride. It cools better then neoprene as well.
That's a pretty cheap price for mohair by the way I think you should go for it.