We were previously on Level3 and ended up switching DC's and Backbone's - I have heard great things about Level3 - but, we just had too many issues (this was about a year ago) - they had all sorts of problems setting up an internal loop with our DC (not ours, but the DC we used) - still not sure why this happened - but, left a sour taste in my mouth - either way - I know their backbone is of great quality - So, Im just assuming this was one of those things - bad luck - whatever - dont think its the norm - but, thought it was worth mentioning...