RobThePilot
Probably not. In today's pilot market with tens of thousands of unemployed experienced pilots the chances of landing a job are minimal. But even in the pilot markets of yesteryear it wouldn't have helped much: airlines wanted either (a) experienced type rated guys with 500 or 1000 hours on type or as multi crew, or (b) brand new cadets with 200 hours ready to be moulded. They wouldn't really differentiate between 200 hours and 900 hours (if anything Ryanair preferred 200 hours - the more single pilot hours you have the harder it is to train you multi crew, apparently)
In the US (assuming you have a US passport as well) - single pilot hours are valued more, as you need 1500 hours for an airline job (with a few exceptions). Also, any turbine hours you have on a US licence wouldn't be worth much in the UK as it wouldn't get you out of the requirement for a type rating over here unless you have hundreds hours on type as well.
Get the licence appropriate to where you intend to finally be working.