To answer my original question ... Probably not ok.
Theoretically, it works. On the downside, it created drag on my Big Dog pump that was obvious. I went back to a traditional install with 1 in line check valve and a 1/8" hole to prevent air lock and it gained noticeable capacity. The primary pump also uses a traditional configuration now.
I'm not sure I understand why screw in check valves are sold. They capture the imagination, but don't work very well. However, the only way you can figure that out is by experience. I'm also not sure how they deal with the potential problem of air lock. I couldn't see any ventilation methods. Perhaps they are not needed with that configuration?