It is interesting to me about 150s running out of gas. I think the 22.5 gallons usable for 150s is just shy of a safe amount. With my aux tank I put in 7.5 gallons and fly with 30.0 gallons usable. For me that is the perfect amount for cross country trips. I can fly without refueling until I'm ready for a lunch break, refill, and fly until I'm ready to stop for the day.
Originally the LSA Cessna 162 specification said it would have 30 gallons, and I thought "Yes, they figured out the right amount." But the latest specs goes back to 25 gallon tanks with the unusable fuel less than than.