Easy choice for me, train on clinchers and race on tubulars. This is always what I have done. I love the comfort and speed that tubulars brings me on race day and I love the fact that they are more puncture resistant. Tubulars are messy and the glue is nightmare but I have learned to master the gluing and the mess đŸ™‚ Here is a good article from Cyclingnews about it.