A "glass cannonball"... that's a new one!
Assuming the laptops are broadly similar in terms of specs and price, here are a few thoughts:
1. The Dell would be the 'sensible' choice. Sturdy chassis but they tend to be more expensive than rivals with similar specs. Battery life is typically 6 to 8 hours of useful up-time.
2. The Zenbook would be the stylish choice. Very slim and light, but their battery packs are still a bit wobbly. When they do work, you should be able to get some 9 to 11 hours of battery life.
3. The Acer would be the gambler's choice. Routinely high on specs, but sadly still low on build-quality. Any malfunction will typically - and at best - result in a replacement machine since Acer have decided not to maintain a...