I'd heard terrible things about the Yankee Agitank, too. Bad enough that I built myself a set of developing tubes (including a light trap fill/drain neck with cap) out of plastic drain pipe.
There are problems with tube development, though (BTZS notwithstanding): it takes a lot of solution if you don't have a setup where you can prefill and roll agitate like BTZS does, is slow to fill and drain (requiring long development times to avoid unevenness), can scratch either inserting or removing the film, and there's a strong tendency to retain antihalation dye on the base side (enough so that I'd taken to fixing in a tray, opening the tubes after stop bath).
With the price of the Yankee tank, I gave it a try -- and it works fine. It fills very quickly if you don't (as I did on my first try) attempt to pour from a small-necked bottle, and drains as fast, it agitates nicely by sliding back and forth (Kodak method) or by tipping to one end and then the other, can be used for stand or semi-stand processing, holds anywhere from one to a dozen sheets, and did I mention it's only about $35 new, often less than that on eBay? If you're a real stickler for uniform development start, it can even be prefilled and the loaded film carrier dropped in, as with most other daylight tank systems (plastic or stainless). It's cheap enough to even have three and treat them like a dip & dunk line.