1. Carefully made a 9 bar selection, snapped to the grid, so that I could cut and paste some audio clips that were aligned correctly but not starting on measure boundaries. eg. Audio clip starts at 8:03:050, so I selected started from 8:01:000. Pasted it elsewhere, and saw that Sonar 'helpfully' changes the size of the selection to starts at the start of the earliest clip, meaning it pastes in at an unexpected position that is no longer aligned relative to measures. Thanks! I had to artificially extend the clips to measure boundaries, cut/paste them, then trim them again.
 
2. Stretched audio (via ctrl-slip-edit) occasionally plays back with major glitches - i.e. peaks of +9.0dB, even +99dB once! Bounce-to-clip solves the problem, but something was obviously broken.
 
3. The first time I hit Play after switching from one open project to another, I often get a high pitched squeal instead of my audio. Occasionally I get no audio at all. Stopping and restarting transport fixes that.
 
4. Snap-offsets getting messed up when I do anything involving time-stretching clips where the underlying audio appears in more than one clip... that wastes my time and requires a bounce, too.
 
All these problems have workarounds, but it's tiring to run into these issues when I'm trying to be creative!

The bug where Ctrl-slip-edit changes the Snap offsets has been reported (I cannot find the bug number) and was taken up by development about 2 weeks ago. It seems to apply to all situations where the start of the audio file and the start of the clip do not coincide.
 
This bug goes back to Sonar 8 (at least) and has probably been the cause of many complaints of inexplicable snap-to-grid behavior.

I may be the only one but the snap stuff is probably the most clunky part of the interface to me. I spend a lot of time enabling and disabling snap, bypassing snap temporarily and especially switching between snap by and snap to. For some reason whenever I use Logic (everyone around me uses it), even though I feel a little handicapped because I don't know the interface as well as I do Sonar's, everything always seems to snap exactly where I'd expect it to without me ever even considering snap settings. I really hope there can be an overhaul of the current implementation.

I agree with you about the clunkiness of snap. Maybe I'm just dreaming of an imagined bygone golden age, but I recall it all being much easier to use in Sonar 8.5 and earlier. But then, so was Audiosnap.

I think the smart grid being on by default throws users when first confronted by it.
I generally know the beat of the song and just set the global and PRV grids accordingly,
thus pre-empting any problems. Sonar 8.5 had no Smart grid.

Kylotan
2. Stretched audio (via ctrl-slip-edit) occasionally plays back with major glitches - i.e. peaks of +9.0dB, even +99dB once! Bounce-to-clip solves the problem, but something was obviously broken.

Real time playback and rendering (bounce to clip) use different algorithms for time stretching.  The version used for real time playback is optimised for speed and efficiency (for real time use). The render version is optimised for quality, less capable systems may struggle to use it in real time.
 
There is a setting (I think in preferences) where you can set which time stretch algorithm to use for each case.

I generally turn Smart grid off - it's wrong as often as it's right, it seems to me.
 
But, hey, I'm highjacking this thread on an unproductive rant, so over and out.

Don't worry, the thread is unproductive anyway!
 
I'm trying hard to get used to Smart Grid but its idea of what the grid should be is rarely what I think it should be.
 
Just to be clear, the first problem I encountered wasn't a problem with Snap to Grid - that part worked perfectly. It's just that Sonar thinks it's being helpful by ignoring the part of the selection that contained no audio, meaning I couldn't paste it an exact number of measures from where it started.
 
And yeah, I appreciate there are different algorithms for stretched audio, but none of them should be producing crazy audio spikes.

I agree there, SmartGrid doesn't usually do what I expect while Logic's does. I end up doing it manually which takes a lot of time.

Kylotan
2. Stretched audio (via ctrl-slip-edit) occasionally plays back with major glitches - i.e. peaks of +9.0dB, even +99dB once! Bounce-to-clip solves the problem, but something was obviously broken.

I've encountered this before. Turning off the 64-bit double-precision engine should eliminate the live playback problem.