I've had one running since mid January, but haven't noticed any leaning issues (it's on an eggcrate/pvc stand in the sump). You might be able to clock the pump slightly in relation to the body so it's weight is counteracting your skimmer's tendency to lean towards the tube side.
As for the skimmer itself, it was pretty finicky until recently. With the outlet closed enough for it to skim decent, it would overflow occasionally. With the outlet opened up, it skimmed lousy and had a lot of build-up in the neck. I've since added a ball valve in the air line between the pump and silencer to throttle the air down a bit (the adjustment on the volute seemed to have no effect). So far, I think it's skimming much better. No overflows, no build-up in the neck, just skimmate. It hasn't been long enough to call it a total success, but I like it so far.