Listening to music mostly on an iPod, like I do, means that I have to seek a balance between the quality of the encoding and the space considerations. In practice, that means I don't mind 128kbps and prefer not to have 320kbps on my player if I have a choice of smaller files. I prefer 192 and above for modern recordings and, say, at least 96 for pre-30s records and things like Hasil Adkins. When I rip my own CDs, the default is high VBR (around 200).
In the last few years it became easier to find and download album N off the web rather than go through my shelves, pull an actual CD out, rip it, tag it etc. etc. I think this trend will only accelerate, so I do not view my mp3 collection as anything permanent to pass onto my grandchildren. What that means, again, is that the music here is only to introduce you to the new sounds, sometimes with an "introductory" bitrate. If you dig it, you can find an audiophile-quality copy (i.e. buy a CD) for your heavy rotation.