Agree! If you have a number of domains and can justify a membership, they Openprovider (NL) is a good option.
Some foreign extensions are quite expensive though. I happened to be looking into that yesterday, and Netim (FR) seems to be a good option for that. For the two extensions I need, they were among the cheapest with renewals.
> Some foreign extensions are quite expensive though.
It's not just foreign domains that are expensive. A quick check showed openprovider charges double of what other providers charge for .nl domains, and the same applies for other european TLDs, even .eu.