CDN77 is a reseller of the OnAPP CDN, and we've used their services to speed up some Euro sites which get Asian attention.
The service was so good, that we almost signed up to provide the OnAPP CDN ourselves, before we choose the solution we have now.
The only issue with CDN77/OnAPP, is that they DO NOT shield your website, but create a mirror URL that your images and static data should appear on, like MAXCDN and similar.
They therefore speed up your site significantly, but offer no protection from DDoS at all. Traffic spikes yes, but not DDoS.