Here in the New York Metro, XO's collocation offering is pretty solid. No frills, but competently managed, and offered under a reasonable pricing model for retail collocation. I've had similarly positive experiences with their transport side of the house. I've not looked at the IP product... I certainly belive the negative XO feedback shared; having heard similar, it would seem there's definite potential to be treated as merely a number. At the same time, our experience has been great, and I'd happily recommend them. I think the quality of your XO customer experience is directly proportional to the caliber of your account team, along with your ability to vendor-manage and assemble a suitable escalation matrix. As for the Savvis suggestion, I'm not sure I'd agree. We're in 2010, yet they continue to maintain a fair number of gigabit-sized peering interfaces, seemingly operating at or close to capacity. HTH, -a