I've previously used modern 7-speed chains for my 5/6 speed bikes.

I've had severe skipping issues with my 7-speed chains and my french and italian freewheels (chain skating over/between the cogs when shifting). Only my Shimano freewheels work with these modern chains.

Now I'm thinking of trying a vintage Regina CX chain that is wider than the 7-speed ones. The good vintage chains are pretty expensive nowadays. For those of you that use these chains: what kind of mileage are you getting out of these chains before they wear out? I only ride a couple thousand miles training and racing on my road bike annually, maybe even less now that I have other bikes. Is the chain wear comparable to modern 7-10 speed chains?

I'm wondering if I should keep using new cheap 7-speed chains and suitable freewheels or switch to a fully vintage setup, please help me decide. I'd love to use these nice old european freewheels that I have hanging around.