I use mechjeb all the time and it works great for me. I do nothing special for lunch, but for when I'm in orbit here's what I've done special. I have taken an added a third OMS engine, on the connection node between the two full size engines and make sure they're trim is set to "0" . If it starts to spin in weird ways trying to chase the maneuver node at the end of a burn just let it, seems to work out in the end for me. I use docking autopilot, rendezvous autopilot, and even spaceplane guidance for landing, as well as everything in between. Let me know if you need pictures illustrating what I'm doing with the engine placement. As to whether to work with a super 25 I would think so they're designed pretty similar. I hope this wasn't too long of a reply. P.s. I can't wait for the super 25