I've been following along a bit .. A few thoughts
1. I can clearly see on the dyno sheet that wasn't a full pull, and it well be well into the 1050 area once it was pulled to the rpm these engines actually make power 7600 rpm area.
2. Its a dyno, if he wanted to make it say 900 or make it say 1200 .. its easy to do, so basing buying a engine off of dyno power is silly, you buy a engine based on the parts you put together. The parts you have there easily will make 950 real power all day. I ran that head out of box on a 548 ci engine and made 967hp with it, you have the parts to make good power.
3. Whats this thing run in a car and at what weight ... that's the true dyno IMO Of course, you have to get everything right to go along with this.
I am not saying you shouldn't be upset, but I am saying if you wanted 1100hp its easy to make a dyno say that, clearly this wasn't what the engine builder was after. With the parts and price you got, it was a steal IMO