Although I like what Stanner does, and he has a REALLY impressive rig, I wouldn't say that "your mileage won't vary" between the 1st Gen and 2nd Gen. Tonally, they are noticeably different. It's totally a matter of taste which you may prefer. I like both for different reasons. Though, if your goal is a massive wall of sludge like what SunnO))) and Stanner create, I think both 1st Gen and 2nd Gen will get the job done with negligible differences.
Really, playing both amps is the only way to know which one best suits your needs. If any of you are within driving distance of Baltimore, MD, you're certainly welcome to come by and give both of them a test drive and decide for yourselves.