what size rims are folk running on their roosters. width obviously....

I don't have a Rooster Tony but I'd recommend getting some Dually's..

I'll be going for Hugo's I think .....

I'm running the 29+ 50mm Sun Mulefut 50SLs (655g) on my Stache, which go tubeless with Chupacabras really easily. I reckon they'd be a good bet.

From the 29+ rim list on MTBR.

Stan Hugo 52.3mm 49.9mm 700g
Surly Rabbit Hole 50.0mm 44.5mm 699g
WTB Scraper 50.0mm 45.0mm 712g
Velocity Dually 45.0mm 39.0mm 675g
Kris Holm 47.0mm ? 801g
Northpaw 47.0mm ? 645g
Sarma Naren 50.0mm 44.0mm 550g
Nextie Jungle Fox 50.0mm 45.0mm 510g
Nextie Snow Fox 50.0mm 45.0mm? 500g
Nextie 40mm 40.0mm 35.0mm 460g
Light Bicycle 50 50.0mm 45.0mm 490g
Light Bicycle 38 38.0mm 31.6mm 450g
Ibis 941 41.0mm 35.0mm 488g
Koroshiro Enso 950 50.0mm 46.0mm 390g!
Travers CR29 plus 50.0mm 45.0mm 510g (Jungle Fox?)
Derby 29er 35.0mm 29.0mm 460g XC/485g AM/525g DH

Duallys on my Krampus Tony...
Spotty Dog IMHO.

I've not taken delivery yet (should be here tomorrow) but went for Hugo's.

Let's see hire they cope with whatever Stu throws at us on the BB200.

Velocity Dually with Maxxis Chronicle.
Sam did a deal with the Duallies in the original Kickstarter, so I guess they are going to be the most common choice.

Duallys with Dirt Wizards. Tubeless pretty easily with some Gorilla tape.

Si

Got Hugo's on my 29er+ Travers Rudy Fat which I've run tubless with no problems.
Had North Paws in the past but couldn't do them tubless.