Jumping into this thread without having read much except George and Mitch's excellent posts. I fully agree with Mitch that the lab-grade temperature control of the BDB, AND it's live real time puck pressure gauge (which surprisingly many glamorously expensive machines don't have), is actually a help when it comes to learning "barista'ing". Once you learn how temperature and pressure play in the cup, it sets you well to then go out and explore more rudimentary manual methods. In fact, one of my mates in the Houston area reports of a coffee shop that uses BDB's for barista training and tasting, so they can learn temperature and pressure.
Not much to add except my testimonial of my life with a BDB as a launch customer, back in late 2011 when it first came out. Bought it from Williams Sonoma during their Fall sale of 30% off anything over $1000. The BDB was $1199 at the time, before the sale price. Besides one needless warranty replacement (that had I known more a the time, was much ado about nothing, literally nothing actually wrong with the machine), it lasted until mid-2018, with only the well known routine maintenance items, replacing a couple of worn o-rings, a solenoid, slow steam wand drip. All easy items that will need attention on any BDB after 2-3 years. In mid-2018, it stopped pre-infusing, even though it still worked perfectly normally as a normal espresso machine. That... was not one of the routine maintenance items. I tried swapping out the pump, (the BDB uses the same widely available, and affordable Italian pumps that most other prosumer machines use), but that didn't fix it. So I paid Breville's fixed repair fee, which includes shipping both ways and a fitted box, so you don't have to worry about how to pack it yourself, and... they sent me back a brand new machine. The moral of this story... do the easy stuff yourself. When something big comes up, that's when you send away to Breville, and they will likely send you back a brand new machine. So now I'm over two years in on this machine. It has become my mod lab. I have it on a remote mounted rotary pump, re routed some of the tubes so now it's flow controlled via the onboard needle valve, de-coupled the solenoid from the pump, so I can operate each independently of the other. Discovered that the Italian solenoid that comes in the machine is of a lower quality/cheaper than some others out there, BUT since Breville uses a standard form factor for solenoids, I put in a more expensive, (and probably more durable) American branded solenoid. Changed a couple of o-rings. Put in an ancient steam ball valve that someone donated to me because it was drippy, but I serviced myself it and it's been working like a champ for the last two years.
To see if you are game for the kind of maintenance required, here are a couple of quick videos, no more than a couple of minutes each.
Fixing the drippy steam valve: