All considered, the Qumi Q7 is a slick LED powered projector ideal for lots of road warriors. It's especially capable for the "new" road warrior, who travels light - works from a phone, or tablet, or a thumb drive. Sound is good for a small projector like this, and the Q7, when packed in its nylon carry case, takes up little space.
The most serious competition will be with the smaller of the business projectors that are lamp based. They will sell for less, but eventually need a replacement lamp, typically $199+ unless you are a school where there's probably a lamp education discount. Most of those lamp based projectors though would have to be described as at least one size larger, and most would be 1.5 to 4 pounds heavier.
If you have a decent smaller room - be it in a school, or conference room, the Q7 may prove to be a very attractive small projector install. A little thin on sound, perhaps, with only 4 watts, but, again, very capable in terms of media players, Wifi capabilities (optional), and almost all the typical portable/small fixed install projectors, except hard wired networking. The Q7 would make a good mount it, and forget about it projector - one that just gets used, no maintenance, until technology bypasses it way down the road.
With all the advanced features - wifi option, media players, etc., the Q7 should be a first class choice for mobile educators, perhaps for specialty teachers that move from school to school as part of special programs.
Heavier and bulkier, are not favorite "features" for those who travel, present, travel present, aka road warriors, giving the Q7 a major advantage over lamp based projectors. And the road warriors who bring their projectors home for fun and games should find the Q7 more than adequate, as long as you aren't expecting serious home theater performance.
You can buy smaller, less powerful pocket - led projectors, but the Q7 has the muscle, and the feature set to be a serious choice for serious presenters, just not ones looking to fill a hotel ballroom.
All considered, the Qumi Q7 should do extremely well for those needing a very small portable projector, or those that just want a modern, MHL compatible, HDMI equipped, Media player savvy WXGA projector for a wide range of uses. And don't forget that the Q7 should do very nicely for a small digital signage projector. All that's left is the list of Pros ad Cons. Good job Vivitek!