We recently evaluated DNS options for our ~800 domains we host DNS for and decided to go with DNSMadeEasy. We're not switched over yet but the deciding factor for me was they're an anycast network and can offer a lot of cool regional responding if we grow to that size. We want to use vanity domains, e.g. ns1,2.ourcompany.com so w/ DNSimple that's only two locations that need to be DDoSed or fail and our sites are down.
It's a fair point (DNSimple is unicast). We're working on building out an Anycast infrastructure, but even that isn't a guarantee for surviving a DDoS. Bottom line on a DDoS: it's a war of bandwidth and the enemy has all the advantages. If you must buy bandwidth and you get DDoS'd you have to pay for that bandwidth, which can be very expensive (not to mention the ongoing operational costs and the ).
Still, we're going to do our best to switch over to Anycast and continue building out our infrastructure as we have the capital to do so.
