ski length question- k2 coombacks

i'm debating on the 181 vs. 188 k2 coomback. i am 6'1'', 178 lbs without a pack, intermediate skier, looking to use the ski for touring and ski mountaineering. most interested in all-around performance so i'm leaning towards the 181. i realize this is largely a question of preference but any pearls of wisdom would be appreciated!

I have never skied the coomback so factor that in, but I would think with your size the 181 should work well and the 190ish length may make kick turns while skinning less efficient. I am not the most flexible guy but I found a big difference between a 180 and 190 while climbing. Of course on those big deep days where you want to stay on safe moderate angles the 190 will keep you up on top and coasting faster.

K2's also measure long (as in the same length in another brand will be shorter). Seems to be the case w/ all K2's.

145#, 5' 8", intermediate+
(& getting wussier as everyone around me seems to be breaking & tearing bones/ligaments)
skiing on 167 Coombacks (which are longer than my karhu 170's).

You could go with either. Do you want more agile or more float? I'm 5'8" 160 and tele on the antipiste (same ski) 174. Actually more like a 181. K2 measures sidecut length on their BC skis. Or at least they did when I bought mine.
They do have a skier /weight suggestion chart, BTW.

I am 6 2" about 190. Get the 181. I love em in corn, powder, chop. One of the best skiis of the last five years.

I am 6', approx 165 (no pack) and have antipiste (with tip rocker) in 188.  I really like the ski/length but typically only only use it inbounds now due to weight.  it's super versatile pow, crust, firm...

If I was buying all over again for BC only, I'd get the 181 and go tlt speed to lighten the load.

marmot is having a demo day at alpental soon and I would expect the coomback to be one of the skis avail as I think it's in their regular demo fleet.