I pondered this same question a few weeks ago as I was considering my first venture into DIY speakers. At the time, I didn't know how good DIY speakers could sound and I was feeling risk averse, so I went with the much cheaper option, the BR-1.

I'm very pleased with the BR-1. I find these speakers have a nice detailed high-end, but the low-end, while not insignificant, is not as tight as I would like it. I listen to alot of classical music, and I like the speakers for solo or chamber music, as well as jazz and pop. But for large orchestral works it is not quite there. A music-oriented sub might help (potential future project).

These speakers did get me excited about DIY, and I think will eventually pursue building the AR.coms. Though I've never heard a pair, part of my motivation is curiousity about how a pair of speakers could have so much positive feedback written about it. I'm not crazy about the Madisound or Speaker City cabinets, so I'm currently assessing other options.