A slightly different angle...certainly buy what you can afford. However, I would consider who you want as a kilt maker first. They will be able to discuss your options directly as well as have additional insight.

that said, I prefer wool as well. It really isn't noticeably warmer than PV and we have been at 110+ degrees F the past week or so "up" here in Oklahoma. If properly cared for, both materials will last a long time.

Final thought, to echo others, take your time to get it right. Otherwise, you will end up not happy and just have a kilt you never wear...what's the point of that?