One thing I should add about using the Motion Prop KP-series amps on stage: it clearly sounds best when raised off of the floor and angled upwards towards the back of your head, as suggested in it's owner's manual. There are a variety of amp stands that'll do the job - I use one by QuikLok. The reason is simple: your body will block the sound of the amp from your own ears if it is not raised and angled. This won't affect how the audience hears the amp but how you will hear it. This might negate BB's idea of leaving it in some kind of vinyl case while playing. At first I tried just tilting it back but found that it sounded muffled to me because my body was blocking it - it sounds much better on a stand, especially because the amp will likely be located pretty close to you on an average stage.

Although the KP-200s weighs 56 lbs, it's comfortable to carry (at least for me, but I'm 6' and pretty strong). I wouldn't add rollers to it but if you need help then a small handtruck would be enough.

I think I mentioned before that I really liked the padded cover that Larry at Lecase made for my KP-200s, and it fits like a glove despite the weird angles of the cabinet. The front of the amp is not protected and would be easy to damage so a cover is a good investment.

And least I forget: yes, I still love my KP-200s and I don't think I've ever seen or heard a better keyboard amp. I think the KP-100s will also perform well but besides the power difference I'd also be concerned about the difference in speaker size vs the KP-200s (2-6" speakers vs. 2-8") and the bass response. Guess we'll find out when you guys get your 100s' and you could always add powered spakers or subwoofers to it when needed, but since I still play with bands on occasion I'd still go with the beefier KP-200s.