Which FFP

Hello!
Can I trouble all you regular flyers for some advice?
I am taking my first flight in ages on a non VS mileage earning airline in March.
We are flying with NW, and I wonder which FFP is worth me signing up to? Obviously it has to be a skyteam one but does one have a benefit over another? (Bearing in mind most of my travel is leisure not business)
For example, If I signed up to CO's, would that be better than signing up to KLM's as CO has closer links with VS? Would I be able to tip my CO miles into my VS account etc?
Any advice would be appreciated!
Can I trouble all you regular flyers for some advice?
I am taking my first flight in ages on a non VS mileage earning airline in March.
We are flying with NW, and I wonder which FFP is worth me signing up to? Obviously it has to be a skyteam one but does one have a benefit over another? (Bearing in mind most of my travel is leisure not business)
For example, If I signed up to CO's, would that be better than signing up to KLM's as CO has closer links with VS? Would I be able to tip my CO miles into my VS account etc?
Any advice would be appreciated!