29ers are fun. tire selection remains limited, especially for gnarly/wet conditions, but its improving. there are many i haven't tried because: a) i bought a house and i'm broke, b) i expect their performance to be predictable based on their 26" versions.
everything so far has set up tubeless quite nicely with stans rims/tape/goo. i ride everything from xc races to gnarly gnar, so most of these tires have been pushed far beyond what they were intended for, and most did just fine.
in approximate order from super-fast to slow rolling:
stans raven 2.2 - 550g
paper-thin, zero rolling resistance, very narrow and low volume (more like 2.1 size). somehow finds a bit of grip out back despite having virtually no knobs to speak of. great rear racing tire for smooth terrain if you're very gentle. survived a lap on overnight sensation on the back of my hardtail, but it was terrifying. not recommended for general riding around here (put a big hole in the tread on its first ride in whistler).
crossmark 2.1 - 650g
feels just like its 26" cousin. good volume, surprisingly robust sidewalls - they look flawless despite being horribly abused on my hardtail all summer.
racing ralph (2.25 "snakeskin" sidewall or normal sidewall 2.4, both 650g)
fast like crossmark, but a bit more traction in all directions. equally scary when wet. also excellent sidewalls.
ikon 2.2 "exo" - 610g
very narrow and low volume (smaller than crossmark 2.1). rides like a typical micro-knobby tire (good on firm terrain). despite the "exo" sidewalls, i cut mine up badly in only a week with holes too big for sealant to seal. disappointing tire.
specialized captain 2.2 with "control" casing - 700g.
awesome, especially as a rear for crazy climbing traction. rolls fast but still has solid cornering knobs. bit heavy if you're a weight weenie, but the s-works versions are all paper-thin and just get shredded around here. so far the control casing tires are holding up well. would be good front xc race tire if you don't like the looseness of most light race tires (like everything above).
specialized purgatory 2.2/2.4 (both "control" versions, 700/800g)
taller blockier knobs, not much slower than captain, and bit more traction in all directions, less scary in wet. very predictable cornering, doesn't mind being pushed a bit. the 2.4 is obese, far bigger than 2.4 ardent - for me its too tall, making it very unstable when pushed hard, even on a wide rim (stans flow).
nobby nic 2.25 snakeskin, 700g
good dry tire, predictable at everything, kinda slow, knobs get shredded quickly, expensive. new "pace-star" rubber is no better than their old rubber for wet conditions, still sucks. i burned through a pair in 2 months, and was glad to discover specialized tires and move on.
ardent 2.4 - 800g
i don't like the ardent, except run backwards in the rear, where it seems to work quite nicely. big volume, very round tread. good climbing traction, loose braking (not much worse than when its run forwards), loose but stable cornering. i've had good luck with the sidewalls, but friends running them with tubes get a lot of pinch flats.
specialized eskar 2.3 "control" - 700g
perfect shape - wide, but not too round, and not too tall that its unstable during hard cornering. like all specialized tires, it measures up to its labelled size. stickiest rubber i've found so far - labelled 55/65 but feels lower to me. widely-placed solid cornering knobs, with shorter center knobs and bit of a transition gap (similar spacing to high roller). kinda slow rolling. very predictable, can be pushed surprisingly hard in corners. feels like a mini-minion. highly recommended front winter tire.
look forward to the forthcoming minion and butcher 29er tires next year. i wish panaracer would make a rampage "SC" 29er for winter riding.
question is, 140mm 29er or 160mm 26er for next summer?