I moved all my services from EC2 to Rackspace Cloud about 2 years ago, but I'm regretting it.

Rackspace Cloud does one thing well - small instances have great value CPU & local IO performance. If your app is CPU or local IO bound, splitting it across multiple 256MB instances on Rackspace Cloud will get you huge performance relative to price. I've been worried that this would degrade as the service grew, but that hasn't been the case.

Unfortunately many other 'features' of Rackspace Cloud have been poor to awful recently. Some anecdotal stories;

1) We haven't been able to make images of our server or restore ANY backup of our servers for months. There is a bug in the backup service where if you have spaces in the names of your Cloud Files containers (completely unrelated to the backup service) then all images fail to be able to be restored. We can't remove the spaces in the containers because you can't rename containers (only delete) and there's too much data tied to different parts of our infrastructure in there.

2) In relation to the issue above, we have had a ticket open for over 2 months which we continually post updates with new information & asking for issue resolution. We never receive updates to the ticket itself and only receive information when contacting their live chat. The response is always "we're working on it". I could live with it if this was a short period, or not an absolutely vital part of their service, but come on - all backups broken for 2 months! No timelines on resolution. No ticket responses. No happy.

3) While CPU value is great on small instances you get the other end of the stick on large instances as other posters here have said. You don't get significantly improved performance above the 2GB servers. CPU capacity certainly does not double as their documents say.

4) Cloud Files latency is awful. Individual read/writes take 300-1000ms. Fine for a small number of large files. Impossible for a large number of small files. (Having said that, being able to upload files and publish to CDN in a click has saved me lots of time for static files I need to quickly publish).

5) Resizing mid to large instances is impossible. We recently tried to resize a 1GB (40GB disc) server to a 2GB (80GB disc) and it took OVER 3 DAYS. No really. It didn't complete. The resize process takes the server down towards the end. We had to get Rackspace to cancel the resize and manually spin up another server and transfer the files ourselves. To make it worse, we couldn't act on this issue initially because Rackspace insisted that the process was "almost complete" from 12 hours onwards. 2.5 days later we just gave up. We managed to do the manual transfer ourselves in a couple of hours. Even worse Rackspace seemed to not think that it was unusual for the process to take 3 days or express any desire to investigate further.

6) The web interface has awful performance at scale. Once you go above 20 cloud servers every single page load takes 10+ seconds. As the original poster says, the number of errors it spits out about not being able to complete operations is insane. It's rare I can go in there planning on doing something and not have to contact support to fix something broken on their end.

7) They're taking the entire web interface and API offline for 12 hours this week! You won't be able to spin up or take down any of your servers. Why? So they can fix a billing issue related to Cloud Sites (a service we don't use).

I've always been a champion of Rackspace Cloud and Rackspace in general, but sadly I would no longer recommend them to people. I'm starting to make contingency plans and looking for other providers again.