I looked briefly at Sonar but only got as far as the website. The problem I had was their website was that it was a bit lacking in some of the details and I got confused a bit on the navigation. It’s a shame since I didn’t even see that it does non-linear editing similar to Live and seems a boat-load cheaper. I don’t know how it compared with the other stuff (include instruments, sample packs) but I would suggest those looking at Live also check our Sonar, as well as Renoise (particularly 2.5 which is in beta testing).
Sadly, Renoise doesn’t do MIDI all that well so it’s probably not a great tool for controlling things like MB-SIDs unless you want to manually muck with CC’s all day. It *does* however run on Linux now which is pretty hot!
As for the MIDI timing in Live, I had a few small issues with my MidiSport 1x1 but they were solved by switching to another MIDI driver, which was a snap in Live. That should all go away once I have my GM5x5x5 ready to go (as soon as like 12 more people sign up for the bulk order anyway
and then I can use just a single MIDI interface for my synths. MIDI timings were actually a nightmare in my version of Cubase though I am sure it has been improved since (or I sure hope so anyway).
The only major issue that is lacking that I miss is that Cubase had a better integrated sound editor. Other than that, Live has a typical DAW view and does the same things basically but seems to have more effects, samples, and soft-synths. Agreed on lack of a demo though. That’s why I didn’t look much at Cubase even though I wanted to. Ableton offered 30 day trial of each Live flavor so, if you timed it right, you could get 90 days worth of usage 
I really wanted to go with Reaper and for heavy audio recording it owns face. So it’s great for a typical alternative rock band perhaps. It has some neat built-in effects but it’s MIDI stuff just was kinda vanilla. It DOES allow you to map both MIDI in and out to different channels, something which sparked me to start looking at a new DAW in the first place. So that’s nice, but otherwise it was a typical DAW and the finished quality of other standard DAWs (ie Cubase) made them a bit more compelling.
I will say that Reaper has a very active community with the developers seeming to be very involved. That’s really really nice to see and I definitely hope Reaper sees some great success.
In the end, I already coughed up the dough for Live so I’m set now
If anyone wants it, be sure to get it by Jan 15th since that’s when the promotion ends (which is $50-150 off depending on which Live flavor you get). That plus the $50 off I got with my Korg nanoKontrol made it not quite so expensive, although it is more than I was planning on spending for a DAW.
I guess time will tell, but I’ve already started making a new song in Live and, unlike Cubase, I was able to escape and worry more about music than everything else. It was really nice so I’m pretty excited about the future with both Live and my SID synth.