OK, I just read through all ten pages of this thread, so I feel justified in giving an essay for a response.....my reasons to answer the OP are as follows:
I started out, as many did, with a cooler and 12" braid, draining by gravity into a boil kettle. It worked well, but I like to tinker and make things, so I built a 3v system (technically 2 vessel, as was pointed out earlier, the HLT doesn't count) out of parts I had lying around (I'm fortunate to have several decommissioned 50L kegs lying around). It worked well also. Then I tried BIAB (for simplicity). Then I tried single vessel no-sparge direct heat mash tun. Then I build a new HERMS. Now I have a 2-vessel RIMS (I use tap water to sparge). It's all home-made using junk or cheap parts, and would cost far less in total than some of the fancy/shiny 'bling' eBIAB systems I've seen. My first comment is that the beer tastes the same from all systems (no side-by-side testing, but no noticeable differences). I like things about all the systems I've tried. Why don't I use the BIAB setup? Firstly, I can't do back-to-back brews as easily (without adding a second vessel, which defeats the purpose); secondly, there's no reason to use it over what I'm using now. I'll pose a question - why BIAB? Space is a valid reason (doesn't affect me); cheap, easy and simple to start if you don't have lots of stuff lying around (doesn't affect me); easier to brew in the kitchen (I'm not allowed to brew in the house anyway...); I can't think of any others. I haven't had a stuck sparge in at least two years. My favourite system was probably the Cooler mash tun - simple and effective. I'd use it again now but my cooler (which again I already had - no purchase needed) can only do 5 gallon batches and I don't want to buy a bigger one for the up to 15 gallon batches I brew (they're very expensive in Australia). The single vessel direct heat no sparge is the only method I wouldn't repeat - there was no time saving (the wort still has to all come to a boil) and efficiency was poor.
Some things that annoy me a bit with this thread:
1. The perception that 3v (in my case 2v) is fancy/expensive/shiny/sexy.....again, some of the eBIAB systems look far more 'blingy' than my homemade setup and any basic cooler setup. BIAB and 3v systems can be simple/homemade or expensive and shiny.
2. That 3v systems are time consuming to clean (including the need to 'scoop out' a mash tun). I carry my mash-tun outside, dump the grain, give it a quick hose out with a pressure cleaner (permanently set up) then put it away. All up, about 3 minutes (surely no different to dumping a bag of grains, then hosing the bag out). Then the boil kettle is the same with either system. By the way, any BIABers who use a dunk sparge are really using a '2v' system anyway!
3. That 3v systems take longer to brew on. It just doesn't (at least IME). It's about the same.
Anyone who says that BIAB is inferior and/or doesn't produce beer that is just as good, is wrong (I'm sure BIAB brewers hear that a bit). But suggesting that 2v is inferior/more expensive/more time consuming/messier is also plain wrong. As the saying goes, there are more ways than one to skin a cat.