I have really only ever used Audio Snap (more than experimentally) to extract timing and intensity of drum hits to midi so I could do drum augmentation.
For example, I record a drum kit, but I only have one bass drum mic. It either goes on the beater side on the other side. So, to get the sound I want, I might extract the midi hits using Audio Snap and then send them to a drum synth and mix the new kick in with the original. This works really well and is very easy. It's better in Platinum even.
Apparently they are working on enhancing drum augmentation further as part of the subscription stuff, and I'm guessing it might be platinum only because of the Audio Snap requirement.
Regarding audio stretching and fixing timing and stuff, I have NEVER done this for a real recording I cared about. I've experimented on practice tracks. I don't normally record with a metronome. I record a group of people playing freely and then set the tempo approximately to the song played. The tempo invariably changes at the start and end of the tune.
I get so much bleed between mics that audio snap and melodyne are practically useless to me.
I primarily use Melodyne just to see what someone has played. Maybe pick out the key changes.