Your mix sounds good to you, but does it sound good to anyone else?
It has been a known problem for some time that a multitrack recording and mix created on one digital audio workstation may not be playable on another - even of the same make and type. Or it might be playable to an extent, but the mix doesn't sound the same, and the timing is suspect.
This was proven recently by a simple eight track recording made on a Pro Tools HD system. The engineer had used a variety of plug-ins, nothing exotic, and in one instance had found the need to apply a time correction to account for the processing delay of a chain of two plug-ins in a stereo aux.
Since the recording had turned out particularly well, I took a copy to listen to on my own Pro Tools system. My system isn't the more recent HD system but its predecessor, the Pro Tools 24 MIXplus system. Despite the fact that manufacturers like to put forward the idea that their previous models are dinosaurs compared to their new range, Pro Tools 24 MIXplus is an excellent system and will reliably turn in great recordings.
Since I had all the same plug-ins, I didn't anticipate any problems in opening the recording. However, when I played it, it didn't sound at all the way I remembered it on the HD system. Never one to trust my ears, I closed the session and went back to the HD system where I bounced the tracks into a stereo mix.
Now when I compared the stereo mix with the multitrack version on my MIXplus system, I could clearly hear the difference. In particular some of the plug-in effects had changed massively. Plainly the parameter values had not translated across correctly.
Now the simple answer to this might be to buy a Pro Tools HD system. But that's just brushing the problem under the carpet. Because from this experience I can extrapolate that whatever I create on an HD system runs the risk of not playing correctly on a future Pro Tools system. And this uncertainty factor applies to any DAW.
Best practice therefore is to print every track including its effects into a single file. You can keep all of the original data of course, but this way you have all of the tracks of your multitrack recording in permanent form that should play correctly on any system. In fact it's probably a good idea to print copies without effects too. Each track should be continuous and not divided into regions. This will remove any potential errors in timing and you will have the freedom to apply any new options in plug-in technology at any time in the future.
My feeling is that this is a serious problem that most people do, as I said, brush under the carpet. Eventually however it is highly likely to sneak out and bite you on the ankle.
You could of course take the Abbey Road approach and keep every multitrack recorder you have ever used, so as long as you can handle the maintenance, you will be guaranteed to be able to play your tracks back at any time. Apart from that, printing your tracks into continuous files is definitely the best option.