Hey Sam. You may want to do a side by side comparison of the sportsman and the Brinsea Ova easy. The Brinsea is the same base capacity and in my opinion more heat stable. I always had cooler corners with the sportsman that I don't get with the Brinsea.
I made my own as well. It's the one that is made from a styrofoam cooler. So far so good. I've had eggs in there for 4 days now and I can see the little embryo in a few of the white ones. Very exciting!
Thanks KS I never really thought about getting the Brinsea...but I have heard about the sportman having cool spots. I might also get one of those cabinet incubators made by dickeys. they are around 400 some but they have been making incubators for probably the longest time.