I just recently moved over from NXT to Paparazzi and I must admit I'm amazed. Excluding some problems with my radio equipment it was really easy to get flying fully autonomously; just earlier today I got everything plugged in. As the airframe I used one of my EasyGliders. It has AuW of 1,4kg and about 400W brushless setup. With it I'm using a 2.4GHz radio which is plugged to the Paparazzi through the PPM encoder; so no need for a PPM radio. Installing the Paparazzi in place included little soldering (10 wires total including the wires to the datamodem) and cluing all the parts in place.
So earlier today I finally got to flying with the PPZ and was hoping for some testing with the so called AUTO1 (i.e. "fly by wire" -mode) but this is what happened; once I had the A/C at a safe altitude I engaged AUTO1 and flew with it some 10 minutes; I worked like a dream right from the start and I hadn't changed a single parameter up to that point (granted, I was using a configuration file that had been made for EasyGlider by another user and I had to make a configuration file for my 2.4GHz radio but still!). Then I engaged AUTO2 and... well... It worked as it's supposed to. I.e. I was flying fully autonomously during my first flight with the Paparazzi. If that's not PnP in the world of RC then what is? (Ok ok.. I had a 35sec flight before this; That flight ended in a crash due to bad 35MHz PCM radio but that's nothing related to the Paparazzi anyways...)
Ok, I have to admit that PPZ with all it's features isn't as simple as ArduPilot, for example, but, still, I wouldn't consider it much harder to use once you get the hang of it. Besides once you get into it you'll get to like all the features that already exist in PPZ code repositories; there's, for example, code for a stabilized camera mount, gyros, additional sensor etc. readily available.
IMHO the PPZ is nowadays much more of a PnP autopilot than people tend to think. One important thing is that all the needed parts are readily available and assembled. As for the price I paid for my PPZ+PPM encoder+Datamodems about 460$ (CheBuzz PPZ
). It's much more than you'd pay for ArduPilot but then again the PPZ is also somewhat more cabable and has much more features although the amount of the features may not suit everyone's taste in terms of conveniency and ease of use.
Oh and one more thing; as you may know the PPZ ground station and pretty much all the software made for PPZ is made for Linux, or Ubuntu to be more precise, and this may sound a little sacry BUT Ubuntu these days is probably one of the easiest and intuitive OSes to use AND install. Especially the installing of the Ubuntu is SO much easier than it is for windows, for example; you can even install Ubuntu while you're still using Windows Vista or XP or whatever and you don't need to format your hard drive or any partitions as Ubuntu will make a new partition for you on the fly which isn't possible with Windows and after installing Ubuntu you'll be able to use either operating system as needed. And if you don't want to install Ubuntu onto your laptop that's fine too: a LIVE CD for PPZ has been made which makes it possible to simply burn the CD and put it into your laptop, restart and you're done. As a side note I want to point out that I actually moved over from Windows to Ubuntu permanently once I had first tried the LIVE CD.
PS. Now that I reread this post I realised that it really sounds like a 2nd class PPZ advert and there's a reason for it too; IMO many people don't really know how easy it is to use PPZ and this can be seen on many discussions on RC Groups, for example. It seems that especially the Linux part is a very powerfull deterrent for many people. But the fact is that using Linux (Ubuntu) these days is so much easier and convenient than it used to be that in my honest opinnion it's actually much better and easier to use than Windows and in many ways much like Mac.