I'm beginning to seriously incline to pre-owned, for the reasons you suggest, for the same reason I chose the Krell as opposed to a Tortuga... if I don't like it, I can 'flip it' and not lose much, if anything at all. There's some wisdom there.
Really the only way to go, IMHO. I've gone through dozens of cable manufacturers in the last 30+ years, and the only way to really know what you like is to listen to it for yourself in your own room, with your own gear.
Buying used you can be pretty sure they are already burned in too. Don't like 'em? Flip 'em.
What do y'all think about XLO? There's a balanced set on Ebay right now for $200-ish the pair. Not sure if that's a good cable or a good price. Your thoughts?XLO are nice cables, powerful, clean sounding. Personally, I like the Acoustic Zen a bit better, a touch more warmth and sound-stage depth, but it really depends on what you like, not what someone else likes.
Also, a word of warning, be careful when buying used cables on Ebay, many fake cables out there coming from China. XLO has had problems with this, and has resorted to putting holograms on some of their pricier cables. XLO is not alone, Audioquest, Tara Labs, many good cable manufacturers have been fighting the fake cable battle for years now.
Ebay is a hotbed for cable fraud.