Dave hi,
I have used Valvoline 15-40 CH-4/SJ, Repco 15-40 CI-4/SL (actually made by Penrite) and Penrite 10-50 GAS CH-4/SL in my bikes. Currently have Repco 15-40 in the GSX 1400 with Valvoline 15-40 in the Vmaxes. I think any Dino or semi synthetic HD oil will be fine, for me I just get whatever is on sale at the best deal when I need it. Would like to try the DELO but live too far away from a Caltex depot, I know they will deliver but that just bumps up the price.
Cheers from Marty