Main highlights: better speakers in the P50, smart features like obstacle avoidance and screen alignment, more picture correction features, apps, and a completely different design.
Both are good projectors for the price. I especially like the P50's picture. I was very impressed with color and contrast. They are, in my opinion, the highlights of this projector. The P50 is also pretty loaded with features and settings--including some very useful smart features.
Compared to the P40, the P50 has a very different design. It has better speakers, 100 more lumens and an overall more pleasing picture. Both have a good picture for the price but the P50 is better. I haven't had the opportunity to try the P60.
Both have their strengths. The Boom's major highlight is its on-board speakers. They are fantastic. And, to my eye, its surprisingly bright. Colors and contrast on the P50 are among the best of any budget projector I've seen.
