Mau Mau: You sound like a shopper. I've grown culinary herbs for my wife on the kitchen counter in her A/G-3 and my seven hole 'Classic' models. I've grown in the seven holes, upgraded 'Classic,' models for about six, going on seven years. I have three of them. I've harvested, dried and cured an ounce to nearly two ounces of my meds in each unit once I got to know what I was doing. 3/4 of an ounce is pretty much average with two to three small plants. I think the best yield I was ever able to get out of one of my A/Gs' was 1.76 ounces, but you have to consider that theses are miniature, table top growing systems. Once I saw that I could keep my sugar bowl full I quit counting.
If you think you're going to be the neighborhood pot king with what you get from an A/G you're likely to be very disappointed. They're great for newbies to learn about hydro growing because with the A/G you get to learn it all; lighting and adjustment, pruning, ambient and reservoir temperature importance, water quality, pH adjustment, algae and mold control, nutrients handling and patience. And I really think I learned a lot, just on a miniature scale.
Make sure you get a seven holes model with a pump in the reservoir and you seal off all the unused holes. Bag the pump either with a pump sock from a hydro store for $7 to $10 or you can carefully wrap it in a short woman's nylon sock like they wear with flat shoes to keep the roots out. Those are $2 a pair at Walmart. Make sure you get the tall 24" arm/light stand and the hood with three high intensity CFL's. I'd stay away from the A/G-6, 'Space Saver,' they're not as versatile.
The newer seven holes models have more sophisticated computers than mine and they usually come with a complementary seed kit to learn on. Get a couple of crops under you belt so you learn on their seeds and not yours. Read everything they have on line and they send you with your unit and you should be fine. If you follow their program it's hard to fail. I wouldn't use their nutes on MMJ, I tried, but I did better elsewhere on nutes for MMJ. Once you've got a couple of legal crops under your belt come back and I'll teach you some things you can do with your A/G to grow our favorite herb. I hope that helps. HSA