I've never heard of 410. To my knoledge all the kits come with 415.
I beleave 415 is metric (accouding to the shops where I like 415 is obsolete as a motorcycle chain and not carried around here anymore.
I was able to get 41 chain in town and was $14 for 10 feet ( that's two chains worth). It is slightly more narrow then the stock chain was but that was fine by me as the stock chain had too much slop from side to side for my liking.
supposably the 41 has a higher string as well because it is mainly used in industrial equipment.
I'm not a chain expert but I did talk to a lot of places the deal with chain all time and I was highly recommended to switch to the # 41 chain do to it strength and better fit for my application as well as for the better fit. all other stuff for cations for the chain are the same as 415.