Just to reiterate what all the others have said. I am a mechanic by trade, as are many of the guys on here. If its mechanical, I can fix it. There is more to porting then that. If you want to give the guy experience at porting a banshee, that's one thing. If you want a good strong running port job take it to someone who already has the experience.
Don't feel bad about going and taking them away from him. I did that exact thing when I decided to do the 4mil over the stock crank after asking some questions of the the shop that was doing the work. They just didn't have the right answers for port timings, spacer pate, which pistons and which domes. The answers just didn't make me feel comfortable with they're experience level. So, I just made up a story that I had sold those jugs as is and was going to build another motor that I had purchased off ebay. No hard feelings, just doing something different.
Good luck,
SP