Yup. Have one, it works. Thanks to live rock, I don't really need the biofiltration so that serves as a backup for me. If you lack live rock, I BELIEVE strictly the biobale will not be sufficient, that you should have wet-dry filtration in that case like a biowheel. Thought I had a reliability problem recently, but I figured out it was only a bit of calcium buildup in the venturi's air intake. Uses an easily replaceable powerhead, so if it fails (that's really the only part that might do so) it's cheap and easy to fix.
I can't compare it to others, as this is my first. I've heard reliable information that there are better skimmers out there (though naturally they're more expensive.)
Know little about stainless steel, sorry...I have a titanium grounding probe, but that doesn't really help you! :P I don't use my heater because of the lights, but it's glass.
Live sand mixed with some normal aragonite, since you're skipping live rock, maybe would accelerate your cycling...but then again, if you're trying to save money, I think you could just cycle the tank from scratch or maybe even get your LFS to give you a handful of sand from an existing tank?
I know this is a little untimely in the thread, but I thought I'd share the link that yanked me from purchasing the BakPak to considering the Remora Aqua-C. It will cost $40 USD more. I can not report to the performance because I haven't purchased it yet. I'm still in my purchasing phase. :)
Interesting review...thanks for the info! Let us know how the Remora works, if you go with that one. Sounds like a very capable skimmer, and especially a good one to have around if you ever plan to upsize your tank. I thought the note at the end about proper adjustment of the Bak-Pak venturi was very interesting...I've noticed precisely what they describe, though the way my skimmer is mounted I don't have as good a view of the collection chamber.