ISP Redundancy. Your thoughts?

Hello,

I just wanted to get a feeling of what everyone thinks of ISP redundancy these days. I have long always required two separate ISP providers for each site because that's just what you did.

In talking with a singular global provider that have been trying to make a case that you can still achieve complete diversity with a single provider by specifying diverse loops, diverse pops etc. In the end you still end up on the same backbone of that provider, but those uptimes are extremely high, and any outage at that level is handled much more quickly than something at the LEC level.

I have never worked for a provider so I do not really have a detailed understanding of "under the hood" of the very upstream aspect when dealing with major ISP's. I am hoping to figure out if a single provider with contracted diversity is as good a buying from two separate providers.