Well I like the Qumi a lot, watching movies like Nemo and Speed Racer, were stunning due to the vivid colors they have. The only drawback of the Qumi is a lack of lumens, it pretty much needs to be used in a semi-dark or darker room.
I'm not sure on the Acer K330, I have the Viewsonic PLED-W500 now, due to the fact that it supports 3D at 1280x720 via HDMI and has more lumens than the Qumi. Myself, I'll gladly put up with fan noise to avoid lamp replacements and fretting over hour accumalation.
But there is plenty of information in these forumns to make a decision for yourself. I know I was concerned about fan noise after seeing the first few videos posted of the 500 lumen LED projectors, where they sounded like a vacum cleaner, but that's not the case. They sound more like those little portable space heater fans humming away blowing hot air in the room.
The fan to me, is a little louder than represented in this video, but it's a good representation.http://www.youtube.com/watch?v=qBhDX...0kJPeQH4zvAk7K