Polarizing filter for Cokin Z-Pro holder

Hi all,

I am looking for the ideal solution for a polarising filter for landscapes using my Cokin Z-Pro filter holder set. Has anyone used the slip-in one made for the Z-Pro holder? It is expensive and the only other one I know of is the new Singh-Ray slip in and this is also very pricey at around £250.

Would the Lee 105mm one work and if so how does it fit. I am not trying to go cheap, but I don't want to re-mortgage either.

Thanks in advance,

Kevin