Yuk! Sorry Ziggy, they do nothing for me. Get a lot of the 'razor' shells washed up on the beaches here though.
I've not tried them yet Sheal, been hunting for them down at Weymouth, but with no luck yet. Think I need a very low spring tide to find the burrows. You need a strong salt solution, squirt some down the burrow & wait for them to pop up.
Had those in Celtic Galicia (Bet you didn't know Galicia is a Celtic country! ). I'd travel back specially just to eat them again. Served with NO sauces though. The best way. Fresh out of the sea. (sand.)
I did, because of the occurence of "Cheval de Frese" on the hill forts there and in North Wales. Going to have to get the tide tables out again now