ORIGINAL: ArcticCatRider

The biggest advantage to dual servos is the redundancy if one of the servos is to quit. Apart from the mixing options, there isn't much you can do with duals on a 40 sized airplane that you can't do with a single. You'll have more weight from the extra servo, hardware, and framing that you'll need for the servo bays. The good news is the 4 Star has a nice big wing and you will not notice some extra weight.

Not sure what is more work...repairing the damaged trailing edge and using the work you've already done, or building bays and rails for the outboard servos.

If you do with a dual set up, tape the servo wire to the extension...or somehow make sure it won't work its way loose. It's too late now for a wire tube through the ribs. Also, as someone suggested...use separate channels in place of the Y-harness if you have it available.

If you repair what you've done, cut out a sizeable chunk of the wood near the damaged area....and epoxy in a replica. Sure, it will tough to get uniform...but it will be a solid and reliable repair.

Not trying to be negative here...but just saw many were quick to shoot down the torque rods. There's nothing wrong with them and they've worked well for a long time. I have used them on planes up to .60 size (GP Ugly stick) without issue..with plenty of abusive flying.