Can I use any of the Garrett Z-Lynk wireless products, such as the MS-3 headphones and the Pro-Pointer AT with Z-Lynk, with my Apex?

Yes. Any Garrett Z-Lynk wireless product is compatible with Apex. If you have another preferred brand of headphones or earbuds, you can still use them with the optional Garrett WR-1 Z-Lynk receiver module.