If someone wants to experiment with the Stacker, I won't try to stop them. The HD Stacker has it's fans and some others who would rail against it. I've yet to find credible documentation of it's performance, so I'm inclined to recommend options that have published specifications.
I just ordered a TVPRAMP1R from Amazon... less than $25.
http://forum.tvfool.com/showthread.php?t=13530
I'm not impressed with any of the rotators available... until you step up to commercial / HAM grade products. If the HyGain AR-40 is within your budget, I could suggest it in good conscience.
http://www.hy-gain.com/Product.php?productid=AR-40
I'm more inclined to recommend a second antenna and tuner:
http://forum.tvfool.com/showthread.php?t=2882 This solution avoids any risk of being stuck with a TV that has to be re-scanned every time you switch antennas or re-aim the antenna.