I meant VSTs and samples. However now, that you mentioned it, there is also a function in many DAWs called Rewire. What it basically does, is connect other DAWs to your current one. Quite common to see a Reason rewired to some other DAW, like Cubase for instance.By 3rd party tools, do you just mean external samples/VSTs/instruments, or are there other tools/plug-ins to be considered? Is in common to need to use external plug-ins, or do some DAWs include all needed functionality out of the box?
The thing I really pay attention to, is how stable the DAW is when handling 3rd party tools.
And yes, most of the time, external tools are required for real pro sounds. I know DAWs like Cubase or Logic love to brag about how well supplied are their libraries... but let's be straight - they have their limits. And believe me when I say, you really can hear when some instruments sound artificial.