CX at JFK is usually more flexible, especially for J & F cabins. Of course, it also help for us (in E+ or Y-) when we have courtesy help with special/heavy tags from ground check-in as extended family member worked for one of the alliance partner - only if we are bring heavy items to Asia. Coming back overseas, we do noticed that even CX is more strict - so a photographer's vest or travel vest with deep pockets is ideal for heavier gadgets, to redistribute the weight to comply with restrictions on carryons.