vmotion between multiple hosts

I have just joined a company that is running 2 hosts on ESXi 4.1 Standard, and both hosts have 1 CPU.

I will be getting a Enterprise licences for both hosts in order to enable storage vmotion, but would ideally like to bump the hosts up to 2xCPUs (with additional CPU licences).

If finances mean I can't upgrade both hosts, e.g, if one had 1xCPU and the other had 2, would vmotion fail? If so, will creating an EVC baseline iron out this problem?

Thanks