I've used a great many deal of different hosters over the years, and had my share of issues with each and every one of them. Even in managed environments, if one of my sites was causing a high load on the server and was killing the rest of my sites, I was getting responses like "we can't really get involved" or "you need to upgrade to a stronger server, this one is not enough for your sites".
Since I moved to Nimbus I've had nothing but great experience with the environment's stability. The problems I had with previous hosters (due to the size of my sites according to them), simply just disappeared, and load issues have been diminished to a barely noticeable minimum.
But it's not just the technical part. Nimbus support is to my humble opinion second to none in the IT industry in general, not just hosting services. I have never had better communication with any company I've ever dealt with. Tim and his team have a great attitude towards me, and I assume that's the case with all their customers as I'm not special to them (or even paying that much money for that matter). Any questions I ask are answered thoroughly and any issues that occur are dealt with swiftly.
I recently had a meltdown with my websites' revenue due to political developments (Greece is in a deep hole of **** for those that haven't been watching the news) and Nimbus went way over standard customer support to assist me during this time.
Dealing with Nimbus I feel like I'm dealing with real people like myself and I consider them equal partners to my sites.