I cannot give you a specific opinion for your case without seeing your films and knowing your neurological examination
Its true that ossiffication of the OPLL is rare in caucasions but is common in asian poulations, particularly Japan. Laminoplast has been more commonly used for ossification of the OPLL when this is the only abnormality. Laminectomy is more commonly favoured over here, and probably the experience is less for laminoplasty given its rarity here. Both have their advantiages and disadvantages,laminecotmy may have an overall better chance of releiving the pressure on the cervical canal, although if laminectomy would be sufficient in your case (due to it being due to OPLL ossification) this may give the same result with less chance of complications.
The trouble is, there is a limited amount of good scientific trials comparing these techniques. Perhaps an opinion at a large academic spine center would give you the most 'evidence-based' opinion - once the surgery is done, there is no going back!