Dimus, IRL, TWS is commonly referred to as "Track While Lie" by the pilots because it is notoriously unreliable. Not just in Viper, but Eagle hornet, etc. It's an inside joke among them. The Viper should have DTT (Dual Target Track) which is supposed to be more reliable. I think the main issue that plagues many of us simmers, is that we have a an idea or expectation about how something "should" work based on experience in aviation or other experience. But I've found that a lot of my own biases have been broken due to the friendship of some great current Viper, Eagle and Growler pilots that I fly with in my group. They don't go into anything classified (obviously) but just the general terms are enough to require a complete paradigm shift of understanding. So it doesn't surprise me that the for a Study level sim, the new rendition of the RDI breaks our expectation of how radars should work. This is something that is actually very impressive about DCS. The radar modelling. They actually take into account even a rudimentary level of RCS.
Yes, agreed about the -5. I believe that is actually in work...