Carv is designed to function with a fully enclosed alpine ski boot, with the insert fitting between the shell and the liner. We have had multiple accounts of customers successfully installing and using Carv with Apex boots.
Due to the repetitive insertions and removals of the liner, you may find you get increased wear of the Carv insert. But this shouldn't affect the functionality of Carv. We suggest that you apply additional adhesive tape (provided in the box) when securing the insert and take care when stepping into the Apex shell.
Please note, the 30-day money back guarantee it still valid when used with Apex ski boots.