I first set up on DO last winter. It was a US center, but I don’t remember which one. I had a number of problems. Most were relatively easy to remedy with a delisting request. However, I was never able to get any email to a Microsoft family address (hotmail, msn etc). My range was always on the uceprotectl3 list with very high incident numbers for the range.
I finally switched to Linode. I looked at Vultur, but I think there was an issue with DNS that made Linode a better fit for me. I now have two domains there on different boxes. One was moved from Bluehost and boy was that a pleasant change. That was late spring. Since then I have had little issue with being blocked. I was on uceprotectl3 for about a week, but it didn’t seem to affect anything. I was also recently blocked by Microsoft but I was finally able to get that mitigated.
Linode support has been very responsive. If you let them know you are running a mail server they can tweak IP stuff to be less likely to be blocked. I Had an issue where Zenbl was listing my IPV6 range. Linode support was very helpful by giving me a more private IPV6 range for each box. They were also very patient and helpful walking me through how to work with IPV6 addresses—I had never really done that before. They had lots of really good documentation too.
I think that anywhere you go, without paying a lot of money, there will be issues. It just seems like they were easier to resolve with Linode.