Regular F sprocket changing?
 

just a general question, is it harmful to the bike to do regular front sprocket changes? reason i ask is it's set up on 15/45 which is ok on the road but sucks off road, but i also have a spare 14 front which is great off road but isn't that good for road work.

so was thinking to just swap them over when i go to play in the muddy stuff, or will it cause wear doing it often?

as simon says but it's not going to cause any damage to the bike just might wear out the chain/sprockets a bit differently or slightly faster but nothing hugely noticeable