Hotboat,

You are running an 800 Teague engine in your F-26. I was under the impression that the Maxworx drive could handle 800hp with no problem. Your saying that you send it in every 20hrs. to have checked. That sounds expensive for the average boater, I'm not banging on the Maxworx drives but if there are defective parts in it after 20hrs It seems a bravo 1 XR is just as strong if maintained properly. Does the MAX upper have bigger gears or are they Merc gears with a beefier Max housing? Maybe your big toe is causing the drive damage after 20hrs. All that said 90% of the threads that I have read on Maxworx drives the owners with boats in our size range and running up to 1k hp love them. People with the bigger heavier boats not so much.
It's really odd that the SCX upper would make your boat handle so poorly. I run the B1XR SC Lower on a Mach26 and in the future would like to upgrade to maybe the SCX but I don't know now. What about the SCX-4 would that be an option with an SC Lower?

Thank You for starting this thread.