When comparing Irrlicht vs Pixel Vision 8, the Slant community recommends Pixel Vision 8 for most people. In the question“What are the best 100% free and easy game engines for beginners?” Pixel Vision 8 is ranked 28th while Irrlicht is ranked 38th. The most important reason people chose Pixel Vision 8 is:
Although it started as a commercial product, it is now open-source.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Lots of examples and docs
Many working examples to study and learn. You can easily experiment modifying an example code to grok in full how the engine works. In the beginning of your learning curve, the example code will offer you many useful code snippets.

Pro Free and open source

Pro Good polymorphic design
If you are considering writing your own engine with openGL, you might want to consider Irrlicht instead. It makes many features of any engine worth its salt easy, including events, serialization, nodes, animators, materials, logging, and animation. Bring your own sound and networking.

Pro Lightweight
Especially if you compile it yourself, it can be very light in memory usage.
Pro Easy to entry level C++ experience
If you want to start game developing with C++, then Irrlicht is a good candidate since it removes most of the complications in game making in C++. It will let you obtain experience in programming and games at the same time.
Pro Support for multiple formats
This engine supports multiple formats for 3D objects and textures.
Pro Free and open-source
Although it started as a commercial product, it is now open-source.
Pro Most customizable
This is the first of its kind, being fully customizable. You can customize the game size, color pallete, sound and more.
Cons

Con Outdated
Obsolete over 5 years ago. While the engine is being worked on with plans for new features and support, the movement is slow, leaving many engines far more advanced in certain areas.
Con Not a game engine
This is a 3D graphics engine similar to Ogre3D. Thus, it doesn't provide any pathfinding or physics support. Support for those will have to be added by the dev.
Con Development has been on pause for a while due to lack of time on the part of the original developer
It's open source, so someone else could pick it up, but no one has at this point.
