I have an XA, XA2 and XA4. My XA2 is currently grounded because I would get occasionally OVER exposed frames..I've heard this can be due to shutter sticking.
I use the ISO setting as an exposure compensation on a large fraction of shots. I'm not afraid to crank it all the way over to 50 with 400 speed film. It's just the nature of auto-exposure cameras...the meter can easily be 3 stops off from what I want.