Definitely shoot both. Shooting IPSC means shooting a lot; most matches are 100-200 rounds. Speed rules. IDPA generally means lower round counts, and because cover and "correct" tactics play a much larger part, the ratio of total time to number of rounds fired is usually lower. In both sports, my gear puts me at a competitive disadvantage, but it doesn't bother me; don't let it bother you, either. You're really only competing against others with similar gun & gear anyway, so don't let the IPSC hotshots with their rayguns discourage you.