Thanks, I hadn't considered the parking actually....
The two main points for me are:
1) I am always on Iberia metal these days (like 6 flights /month easy) and I see other IB Plus Sapphire card holders being invited to sit up front and I am always passed over.. I once asked why, and I was told that preference is given to IB card holders over other alliance members.
2) I cannot get the BA Credit card to earn avios as a I am not resident in the UK, I guess I could get the IB one and transfer the points, but one can also get some other benefits with the IB card and IB Plus.
So I figured perhaps I can higher faster with Iberia on an Iberia Plus membership.
A.