Wow - you sure picked two very different reels to puzzle over. Not that you would ever put a Spey Co reel on a tarpon rod, but if you did - I believe they have an anodized finish that could stand up to the saltwater. Not positive on that though. Of course the Galvan would be most practical - but if I got a vote I would vote for you to buy the Spey Co. reel. They are just cool and there is something to be said for supporting passionate craftsmen who make quality products. And - if you were considering this from a monetary/investment point of view then you should definitely go with the Spey Co reel, far more likely to retain its value and/or become a family heirloom.