So after a grand total of 5 rides, the new bike has a reasonable dent near the bottom bracket. No falls, so I can only assume it's a rock strike. It's about 2" away from the bottom bracket on the underside of the downtube. About 1" long, 1/2" wide and maybe 1mm deep, running along the tube rather than across it. It's on heli-tape, so the frame isn't punctured or scratched. Not near any welds either.
Are these things terminal, or is it a case of suck it and see and I'll still be riding it 6 years from now?