James
Perhaps folks are interested in knowing *WHY* VOIP would be hard pressed on a Linode (read bottom of post).... I haven't seen anyone really detailing specifics, other than the kernel module (ztdummy) limitations, which is not really a show-stopper in and of itself. You can run Asterisk in a Linode, but your not going to see certain things working like MOH and even IAX can be effected. OK, so add ztdummy support and your still going to see less than optimal conditions unless Linode re-engineers their core technology.
What is interesting is what your previous citation is essential irrelevant to the discussion, because such things would effect even dedicated server folks, not just VPSs. QOS/TOS has overall been of little concern once packets are on the WAN, its more of a concern with LANs and giving priority to VOIP traffic on limited bandwidth connections.
Whatever makes you feel good

Just adding some enlightenment to the discussion and making people aware of things beyond what has been mentioned.