wow! and some questions...

[BrianG]

Yes, lock-tite will work. Some people can get away without it, but it won't hurt to use some.

Are you sure it's actually cogging? On the BKs, it will cogg a little at really low speeds because the ESC is having trouble finding the rotor position. Once you get some speed, it runs fine (as you've seen). You can minimize this a little by gearing down so the motor isn't as loaded, but you'll lose top speed obviously.

With BL, a slipper is more to protect the drive train from sudden changes (like landing from a jump WOT) rather than to control a launch. If you loosen it enough to have a gentle launch, it will slip too much. Most tighten it so it doesn't slip at all under normal running.

Set the reverse/brake EPA of your radio (if possible) down to like 60%. That should help tame them a bit.