I agree that singlehoming to a good tier-2 provider is much better than being singlehomed to a tier-1 of any quality; It's not so much the support I fear as th

I agree that singlehoming to a good tier-2 provider is much better than being singlehomed to a tier-1 of any quality; It's not so much the support I fear as the... as you said, depeering. (of course, if you are looking for and willing to pay for serious bandwidth, you want to look for three or more upstreams. And in that case, having 3 tier 1 providers is better than having 3 tier 2 providers, as you are less likely to get route overlap, and tier 1 providers, all other things being equal, usually have better latency.)