Ramnode's panel is SolusVM which isn't as good as Linode but their performance blows Linode out of the water. They have ipv4/ipv6, multiple locations (Atlanta and Seattle) and a good owner who seems very open/honest with customers. I expect we'll see feature enhancements as they grow bigger.
Gigenet Cloud has multiple locations (Chicago and Los Angeles), ipv4/ipv6, good performance, good custom panel and a company that has been around for a long time. They use a SAN for all their nodes. Overall one of the most underrated cloud providers out there. (Note: I got free credits for beta testing their cloud)
DigitalOcean has multiple locations (San Francisco, New York, Amsterdam), a decent custom panel (would like to see more statistics and it seems a good staff. They did have a security issues that they seemed very open about (https://www.digitalocean.com/blog_posts/resolved-lvm-data-is...)
Other hosts I have tested/used but did not choose:
Rackspace - Excellent panel, ho-hum support/performance. My biggest issue is they lock instance throughput and refuse to change that. If you have a 512 instance you are locked to 20 mbit which doesn't make sense as you are billed per GB. I asked to have this unlocked as my instances push more and they refused.
Amazon AWS - Great interface but the lack of ipv6 (unless you buy ELB) and poor performance had me look elsewhere.
Others tested/used:
Joyentcloud, Terremark, Zerigo (Was a long time customer but they went downhill when 8x8 bought them), Voxcloud, Cloudsigma , Azure, HP Cloud, Stormondemand (Another good cloud provider that just didn't fit with me), VPS.net, Gandi
