I've used the PLS 5 a lot back in the sheet metal days, that thing worked awesome. I personally have a 5 way black and decker, it was around $200 I believe, and it worked just as well for what I needed. Of course it wasn't ultra precise, but honestly less than 1/8" over 50 or 100 feet, for duct, who cares.
I'm not sure if this is the type your talking about though...
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