Walbro pump is not rated for, or warranteed with, diesel fuel use (per a direct conversation with Walbro). I've had guys call me that had brand new walbro pumps fail in just weeks, other have had them go years. That's a crapshoot for sure, I hope whoever you are getting these from is telling you this, and letting you know that if you send a pump in to Walbro for warranty repair and they find diesel fuel in it, no warranty.
You couldn't talk me into selling someone an AirDog II, I'll never take another phone call from an angry ADII customer that's stuck on the side of the road. I've had more of those fail than Fuelab pumps fail, hands down. I've seen melted wiring harnesses, melted and bent in half (but not blown?) fuses, and failed motors. I've talked with numerous people that have had 2 or even 3 motor replacements in their ADII. The original AD (low pressure) line has always been rock solid and reliable. The ADII doesn't live up to the reputation of the original AD, but is trying to ride on it's coattails.
A1000 is another billet race pump. The simple truth that everyone seems to want to ignore is that with "race parts" comes "race reliability"...period. The same goes for Fuelab, though I've had a LOT better luck with Fuelab than I ever did with the A1000.
The Fuelab pumps have had some issues. Every single pump I've sent back was a circuit board failure, not a pump failure. The ONLY exception was a pump that had a piece of foreign plastic lodged inside. When that was removed, the pump ran perfectly...that was the fault of a "no filtration installation". Fuelab recently switched circuit board shops because of the problems, and they have covered every pump I'm aware of (or that I had anything to do with) under warranty.
I have told everyone that has ever asked me that if RELIABILITY is what they want, "dual parallel stock pumps" (Bosch pumps, not crappy copies from the parts store) is the way to go. Of course, the reality of that situation is that most of the people in the situation of needing these big pumps have done enough "performance work" to the truck that just changing the fuel pump doesn't really change their odds of having a "high horsepower related" breakdown. I know that's not what the interweb says...
