The question that seems to popup a lot is whether or not to get a lift pump.  What happens if the lift pump fails, am I stuck?  Can I get filters anywhere or is it online order only? Why spend the money? How long will the pump last before it needs to be replaced?  Do I need a sump installed on my tank if I get a lift pump?

Here is Airdog comparison with FASS

Here is FASS comparison with AirDog

I personally owned both the Air Dog on my 2005 GMC LLY and the FASS on my 2007 GMC LBZ.  Before I get into my personal preference, let's go with the fact checker (side by side)

Airdog II 4G

• Brushless Gerotor motor; longer motor head (low amperage)
• Adjustable pressure regulator
• AirDog comes with 3/8" fuel ports
• AirDog comes with a plastic pickup tube
• Quick connect line fittings
• Generic Bolt on mounting bracket
• Self priming for easier start-ups
• Demand Flow Fuel Return
• Typically doesn't require a sump (especially on the 15-16 LML Duramax models)
• Lifetime warranty (if purchased at MAP price and from an authorized reseller) *amazon/ebay are not considered authorized
• 25 years in business with the original lift pump design and USA MADE

FASS Signature Titanium Series

• 2 micron filters with the new water separator design to trap the water instead of having a drain
• 2% failure rate on all pumps and has designed the new "FASS Whisper Technology" to make the pumps less noisy. 
• FASS comes with 1/2" fuel ports
• FASS comes with a steel pickup tube
• FASS provides the heater kits for cold climate vehicles
• FASS comes with a rubber isolator pad that goes between the bracket and frame for noise / vibration isolation.
• Has radius cutting feature that prevents stagnant fuel pockets from forming at 90-degree bends
• Bolt On brackets designed by vehicle
• 19 years in business and USA MADE
• Lifetime warranty (if purchased at MAP price and from an authorized reseller) *amazon/ebay are not considered authorized
• 30,000 Mile Filter life