U2 is a 5 watt flashlight. To determine the best 3 watt flashlight for your needs, you must provide more information:
- what runtime are you thinking of?
- which kind of batteries? (regular AA/C/D, lithium CR123/CR2, li-ion)
- reflector of optic?
- hard anodization required or not?
- want to have any special features? (multilevel output, strobe,...)
- how much do you want to spend?