Update: I checked out a Laguna 1836 (I'm considering the 2436) and PM3520C side by side today at Woodcrafters. My observations:
Powermatic vs Laguna
The Tool rest locking mechanism PM
Tool rest design PM
Banjo *tied*
Tailstock PM
Removable control box with speed readout PM
Spindle lock PM
Bed ways Laguna (stainless and wider)
Weight/ease of moving headstock Laguna
Handwheel PM
Laguna: Spindle Height w/ wheel kit (optional) 46"; spindle cone beyond housing: 4"
PM: Spindle Height w/ riser blocks (standard) 46", spindle cone beyond housing: 3"
Availablity: end of May for Laguna 2436 and the PM is in stock. The 1836 is in stock, fwiw.
Price: $4000~4500 PM, $3800 Laguna
The PM tool rest locks so easily and won't budge - love it! I know there is a workaround for the Laguna by adding a 2nd bolt in the available 2nd hole but still.