I'd go with the unicolor drum. I picked one up about a year ago with the base for about $25, after years of tank development. I haven't looked back since. There's a nice little article on the large format page describing how to process 4x5's in these (though I suspect you've already read it). I have had absolutely no problems with uneven development. The really great thing about these is that they use so little chemistry. For the cost, you might as well try one, if you feel it is insufficient, you can still buy a Jobo without losing much money. As far as the btzs tubes, they don't let you work in light and I think they're a bit overpriced.