I actually just checked that out on my lunch break! Pretty informative!
And I know the differences are minor. It's more of a desire to give it a try to see how I like it. I should prolly check out a local brew club to actually witness a 3 tier setup. Who knows. I may like it better than Biab. But I enjoyed Biab more than extract so far. At least for this one time I have done it. Not knocking on extract, I just felt like I was a little more in control of the process.
Start simple and work up to it. That was my plan. I figured I'd use that equipment for while then get a big fancy setup. But I never found a reason to do that! If you start with a setup like mine, you can start doing AG easily and inexpensively. And nearly everything there can also be used for a bigger setup if you decide that's what you want to do.
Never found a reason to upgrade either. I love the simplicity and consistency of cooler mashing (and dennybrew.com, too).