My new bike has some nice lightweight through axles which need Allen keys (different on each end, which is weird). Can they be replaced like for like with the quick-release Maxle tool-free ones or is there something I need to know about?
Brand x do some. Got them on all my bikes.
These fit rockshox boost.
15mm - 110/158/11/M15*P1.5
different on each end, which is weird
A set of Allen keys usually only has one of each size. If they used the same size on each end, you'd need two of that size.
Different on each end of the bike!
I've had lots of bolt up through axles come loose, but very very rarely any maxle lever tool free.
DT Swiss does RWS axles in various sizes. No idea if they'll fit your needs and not quite a Maxle, but I've always got on well with them, at least since they upgraded the handles to alloy from quick death plastic:
https://www.dtswiss.com/en/components/hubs-and-rws/rws
I have a DT one on my Salsa.
Are they all compatible?
Are they all compatible?
No, there's at least a couple of different thread pitches in use, annoyingly.
molgrips
Are they all compatible?
Far from it
Wolk Tooth and Robert Axle Project all have useful info to figure out what you need. Then you can go buy a brand-x to suit.