Had been running into issues with the MJ2 landing autopilot, so I performed a test by bringing a simple lander to a 100k orbit, then telling it to land at KSP.

Running with MJ2, the initial deorbit and correction burns were spot on. After it auto-coasted to the next correction spot, it just got further and further off, burning up fuel I needed for braking to "correct" in the wrong direction.

Swapping out the MJ2 part for the MJ1 one (same case, same location on the same ship, same orbit, etc), the landing autopilot gently set me down on the VAB.

Yes, we know about this problem and are working on debugging it.

Should be fixed by e48c8e4. Try it out in the next release.