I'd say the Wallytractor is so expensive because each one is made for a specific tonearm (effective length + overhang), and lovingly etched by Wally himself (mine is signed and dated). IMHO, there is NO other alignment device that gives the level of precision and accuracy of measurement that the Wally delivers, and you are able to select between both Baerwald and Loefgren alignments. I used to use a Dennesen, and the difference is not subtle. Obtaining a Wally (and having the patience to use it correctly) will be one of the best upgrades a serious analog listener can make.
-R.
-R.