Although I have played some of the games such as Deus Ex, the Unreal Engine seems to heave some unreal drawbacks. First off, one has to know Visual C ++,. Second, the prgramming is basically for a PC and the engine isn't available for MAC users, so if programming for something like real estate then I would stick with QTVR. Lastly, was cost, I can't seem to find a price tag on the engine itself, but on the technical page for new programmers (which can be found here: http://udn.epicgame.com), they recommend nothing less than a Dell Pentium 4, flat screen, a gig or so of RAM, etc. In other words...the most high end PS one can think of. For somebody just getting int VR, I would think this would be an unusually high cost and would definitely not recommend commiting one's resources for that kind of expenditure just to try out a piece of software. Besides, if I were to get a new system, it would have to be a G$ Dual Processor, Dell still can't compare in that department. Cheers. DDoug