Jim,
I am a dealer for Amsoil and currently I am offering some special no-tax deals for members of the WBC.  ($17.50 per gallon) I can arrange even better deals on bulk purchases by the barrel.
For almost everyone in the club running a two-cycle outboard, I would recommend the Amsoil 2-cycle Injector oil.  This TCW III oil is perfect for oil injected outboard engines.  For premix situations using the injector oil at the manufacturer's recommeded ratios will work great.  
While Amsoil has several two cycle oils available, unless you are running an extremely high revving engine with very high compression ratios, the Injector Oil is the ticket.
I have been running Injector oil in my outboards for several years now as have a couple of other members.  The results have been exactly as Amsoil promised. 8)  Less smoke, cleaner burning, negligible carbon build-up in the combustion chamber, and biodegradeble to protect the enviroment.
Call me at home (check member's roster for the number)over the weekend if you want more info or try my home e-mail jjsmith.wa@netzero.net.
On weekdays I can be reached at 425/430-7662 or email jsmith@ci.renton.wa.us