Terry be careful you don't cross the line with blatant advertising for Jetmac ( unless you have already contacted the admin to arrange to be a paid advertiser) it annoys the companies that do pay
But back to your post, I build my own machines and I'm often puzzled why company don't go over board when using belts and flexible coupling, I used a Fenner flexible coupling on a machine with a 24hp engine the coupling I used was rated for a load over 80hp.... it lasted for ever!! Ok it cost twice as much but in the whole build cost it was negligible, I have done the same with belt driven machine.
Are costing of machines so competitive that you need to be frugal with parts?