for my earlier review.
I've used the 10 gallon gas system for a year and a half. Still works great. 64% efficiency is usually dead-on, my minimal water adjustments include diluting with distilled water, adding Lactic Acid, or 5.2pH depending on the recipe. That efficiency might seem low, but with our sized batches the cost difference is irrelevant to me. Predicting OG is much more important.
I could probably fit 39 lbs. of grain into this, so that's pretty much the only upper gravity limitation. No different than any other system. Need more gravity, either use a bit of extract in the boil, or make a slightly smaller batch as someone has already suggested.
Setup and breakdown are very simple. One thing I miss from my multi-burner setup is the ability to heat water for a PBW solution to clean out the mash tun while the boil is under way. There is a loss of time efficiency because of that, though all I would ever need to do to make up that time would be to get my second burner out, or use use cold water and get over it.
The T.O.P. gas controller was a great but $$ addition to the system. It is badass the way it relights by itself if a gust of wind comes by to knock out the flame. Because the BE uses the burner's short legs, and I'm not getting any younger, I really appreciate not having to stoop down to the ground to re-light the burner repeatedly throughout the mash.
There is a lag of several degrees between the mash temperature and the temp of the wort coming off the pump. No big deal, I usually up the controller temp a couple degrees to keep the mash temp where I want it. The variance in temps depends mostly on the rate of recirculation out of the mash tun. Blichmann's false bottoms can take a whole lot of flow without sticking, and I have the 1.5 gallon/minute orifice installed in the output of the mash. I might try the 1.75g/m orifice just to see what happens. The variance also depends a little on the mash volume...a bigger mash will have a little more lag. You can also gently stir the top portion of the mash to help even things out, but I generally avoid doing that. Also avoid over-crushing grain to avoid a stuck mash. My LHBS's grain mill crushes finer than I prefer, so I crush all grains myself.
The Blichmann false bottoms are really great at trapping bits of grain. No matter how much I spray them, there's always something stuck in there. I've come to spray off as much as will come off easily, then let the thing completely dry. Dried bits of grain are brittle and fall right out with the touch of a little brush.
There are certainly less expensive ways to go about brewing. This system was particularly attractive to me because I already had both kettles, Therminator, pump, and false bottom. To finish it all I needed was the adapter lid kit to mate the kettle and mash tun ($250) and later, the controller. My Therminator and pump are mounted on the little stool, with the pump hanging from the bottom step and covered with a cut-open PBW jar as a splash shield.
The TopLink software and controller cable have worked very well. But I don't usually do complicated mashes so I typically set a timer, then change the desired temperature manually on the controller.
I love the system's small footprint, but my brewing habits seem to abhor a vacuum. Since my brewing space is a patio with no table, I use a rolling cart for my work space. There is a power strip bolted to the end of the cart which supplies power to the operation (controller, pump, computer, cell phone, Bose speaker...I like my conveniences) from an extension cord, and my pump is plugged into its own grounded switch http://www.amazon.com/GE-25511-Grounded-Switch-Version/dp/B0113VTPSW
so I can turn it on and off without unplugging it. The controller and most of the hardware roll in and out from the basement on the cart, which saves time and many footsteps when putting away.
Happy to answer any specific questions I might have missed. Good luck!