I like that it's easy to register domains, no additional software needed for Linux or Mac OSX users (which makes sense).
The interface isn't very user friendly so you have learn how DNS works before registering new nameservers which could be confusing at first but really not too hard once your familiar with it. If anyone was looking into this product they should know there are better products out their such as GoDaddy who offer more features than yesnic in addition if price wasn't an issue then godaddy would win hands down! We were using another registrar which had some issues when we moved over from our old hosting account where all of my websites resided onto AWS EC2 instances. It took me about 2 days just learning everything through trial & error until finally getting things right without downtime during migration process.