I have it on good authority that the boat will be running a Zen (as it has during shake down)..
Me, I run a Zen 7 it starts easy, revs hard and high. Glenn, I'm sure Dave would be only to pleased to lighten your wallet, £280 or thereabouts for epoxy I believe.
CMB sparky seems to have had a few teething troubles, most now solved reputedly. Other option could be the SG35 from Italy but that also has had teething troubles.
No competition for me, the nearest O race to me in Sweden is 6 hours away.......not enough time and hard to justify the money......