I think that 38 super comp will give you a lot more options to play with as far as loads go (especially bullet weights) if that's what you're into. 9Major is not as economical as it used to be, but I still save some money and have a little more options than buying 1000k new starline every three months like I used to do.
I do not reload my or anyone else's 9Major brass after it has been shot. When I've been desperate enough for brass and tried to use them, the number of cartridges that failed to case gauge went up dramatically and more than the average number of case head separations seemed to happen.
I should disclose that my open guns are 9Major now and I do not have plans to go back to 38 supercomp.
+1 to this. My competition guns (even production) have become very personal to me over time. As you shoot and compete with it, your open gun will become tuned to you and you to it. If you shoot your open gun with IPSC regulatority, you will wear it out. Starting a relationship with a good gunsmith early will pay off in the future. There is some sort or magic or genius that our best open gunsmiths have that is impossible to replicate in your garage and even in the factory.
High Performance = High Maintenance.
My experience is that every gun is different. You have to try it out. Sometimes you get lucky, sometimes you don't.
FWIW