I'm not going to read through the whole thread to check if anyone else has made the same points, but what immediately struck me was that if I'd had as many problems as this guy says he had with Sonar then I would have accrued way more than 33 forum posts (not including this one) in trying to rectify them. From another thread I read it seems clear that the guy didn't really make much of an effort to learn the software and clearly expect to be able to transfer his FL workflow to Sonar with far less effort.
I get it, learning a complicated program is frustrating as hell when you don't know your way around it. Most people charge right in and feel that their awesome technical skillz will be enough to work out what's what. I went through lots of frustration learning Pro Tools and then I went through even more frustration when I switched to Sonar. What seems like second nature now was incredibly confusing when I first started and it's so easy to channel that frustration into a raging hatred of the program and everything to do with it. Try learning Adobe Illustrator or Premiere without a thorough reading of the manual, a textbook or video course. You will put your fist through the effing screen before the day's out, guaranteed. You will curse Adobe and their backwards ass way of designing a program, which clearly doesn't work correctly. Then you take the time to study how they work, and it doesn't seem so backwards ass, in fact it turns out to be quite positively forwards ass.
I work primarily with MIDI and synths, but also some vocals and guitar. Sonar is versatile enough to approach music making with a building-block style philosophy in addition to the traditional track recording method. I use both approaches interchangeably and mix building blocks with long drawn out MIDI improvisations and audio performances. Ultimately I bounce everything to audio and then work with audio clips, switching back to VSTi's and MIDI if needs be. If you learn the software thoroughly then this workflow is not only doable, but very easy. Sure there are many improvements I'd like to see, but there's not a single DAW out there that has all of the features I want. Sonar has most of them, though.
This guy is perfectly entitled to his opinion, but we're also perfectly entitled to our opinion on his opinion. Personally I think he's quitting way too easily, especially in light of the investment he's made. If he stuck it out and made the effort to work through his problems I can quite easily see him looking back on this thread with embarrassment in a year's time. Or go back to Fruity Loops, whichever.