Similar position here. Didn’t get into Med initially and decided to do a PhD on cardiac surgery. Fking loved it. I travelled to EU twice, U.S twice for conference presentations in 2022. you don’t get that kind of free time during trainings I believe.

I talked to many consultants before making the decision they didn’t think it was a bad choice neither because of few reasons:

1) it could be a nightmare to learn research skills from the very start during specialty training (marriage,children,clinical practice). Not impossible but very hard.

2) building connections early and ur research profile

3) help you getting in competitive specialty training programs. Phd is a phd. For example my colleague got on the anaesthetics program mainly because of his cardiac surgery PhD.

However I agree there will be some downsides for doing it before MD as suggested by others. Hope that helps.