Yes, I was pleasantly surprised that for my all-mountain ski, the shorter length was a dream (it took a few runs to get used to the "decreased stability".) It wasn't decreased stability, I was just using the length as a crutch. I can ski the shorter skis much more centered and balanced, and they are certainly not an inappropriate length at all--they come to my eyebrows when I'm wearing socks! Now, a true powder ski will be longer for sure, but will only be used for deeper powder. Otherwise, those 88s in a 159 are an all-mountain machine. I've skied with a ton of L3's and examiners the past two seasons, and guess what? They KILL it in any snow on 88s and narrower. Now, in TRUE powder (say, 1 foot or deeper) they do tend to drag out the powder skis. But they don't NEED to. I tagged along in an instructor clinic last season when it was dumping snow, and there was 15 inches of fresh, and they were ALL on 88s or narrower. Hmmmm, maybe the professionals actually know what they're doing?
I think in internet land, we get so wrapped up in chasing the latest and greatest, and drooling over powder and powder skis (which, truth be told, we don't get to ski THAT often) that we tend to think that new skis will somehow make us ski better. When in fact, what we need is a ski that feels good to us in the majority of conditions we ski regularly, then go ski them--over and over. I know I've been very guilty of chasing the holy grail of skis...maybe I'm just lucky that I was able to test (demo) the Black Pearls in a HUGE variety of horrifying and lovely conditions over a two day period last season (three--2000 vert runs total) and knew that I'd found "MY" ski. So, maybe I FOUND my holy grail, I don't know! All I know is last season, even after I got the BPs, I'd drag out the Santa Anas with one ounce of fresh snow, then I'd adapt to them, then go back to the BPs, then have to readjust to them. Then I'd constantly be wishing I had brought "x" ski. It was kind of stupid.
I will also say, the 100mm skis were absolutely harder on my knees, even in powder. Still are. I brought out the new Sheevas last week when we supposedly had about 6 inches of fresh, which turned out to not be so, and I was wishing for my BPs.
I don't know. We're all different. But observing expert skiers skiing on true all-mountain (and narrower) skis, that are skis available to use mere mortals, really got me thinking. Pick a pair you like, that are suitable for most conditions, that can help you learn to carve, and go SKI them! And demo in conditions you'll encounter the most.