But as with any suspension upgrade work out what is missing, what you want from it and what you want to play with. Then see if the choices available do what you want.
I’ve never been able to get the fork to feel how I think it should feel. Whether that’s because the damper is old and I’ve been spoiled by newer forks, it’s broken or it’s just badly set up, I can’t say for sure. Always good to get info on if other people have upgraded and what difference it made though.
Don’t forget import duty and VAT on the avalanche
I live in Canada, so still duty etc but Canadian border folk seem pretty hit and miss on collecting in my experience so far.