Just out of interest. Is it sealed worse too?

Be very surprised if it was, not all Deore ones are interchangeable!

I doubt it. Best bet to find out is to look at the shimano techdocs for both hubs and see if the code for the freehub is the same.

http://techdocs.shimano.com/techdocs/index.jsp

IME road freehubs are not as well sealed as MTB hubs. But if they are the same model number, chances are there is no differences.

I had to scrape off the mud and have a look, and it’s a M525. Given that they’re only a bit over 20 quid on CRC, seems pointless to buy a spare freehub body alone. Have bought the whole lot and therefore get bearings, axle, bolts, spacers and a skewer too. And a desk tidy.