It seems like more people post to complain about providers than to report good results. It's hard to choose a provider when you can find somebody complaining about almost any of them. I've been using BlueVM for a bit, and am quite satisfied with them. Considering how little I'm paying for these servers, I'm extremely happy with the service and support I'm getting from BlueVM, and am happy to recommend them to others.
I have two KVM virtual machines with BlueVM, running low-volume email servers. Those two required several reboots in the first few days, but support was responsive, and those servers have now been completely stable for a month.
Yesterday I ordered an OpenVZ VPS from BlueVM to experiment with some VPN software. PPTP worked well, but IPSEC requires a kernel module that didn't exist. I contacted support, expecting them to tell me that it just wouldn't be possible for me to run IPSEC in my VPS. A few minutes later a technician contacted me to tell me he had moved my container to a "testing" version of OpenVZ that is supposed to permit IPSEC, and that he'd love to hear whether I could get it working. Sure enough, I was able install racoon and xl2tpd in Debian and connect to my VPS using the built-in Mac OS X IPSEC client.