In the time since the original post, the price has been dropped, the service has gotten regular updates, and the whitelist cap is irrelevantly large. Even with the changes, Realms offers a poor value for the asking price. He's not personally responsible for resolving bugs in the base game.
We were mad about it not letting us play on 1.8, but we decided to still play it.
Apparently, when it changed to 1.9, all of our worlds got corrupted, so we lost them.
This might not seem like a big deal, but I can almost promise that you will NOT have all 10 slots full at any time, and if you do those occasions will be extremely rare.
This is also the reason Realms will kick you off after a few minutes of inactivity.
I'm willing to bet your players will, too EDIT 5-31-16: I wrote this blog quite a while ago, and have not used realms since, I can't be confident that all the information presented is still accurate. As some as my readers pointed out you can get a free minecraft server. Parent here, doing research on Realms, unfortunately, this post is the number one result on a variety of unrelated queries about Minecraft and Realms.
For future readers: the issue described appears to have been resolved in 2016.
For .00/month I could have Yes, Realms is marginally easier, but you're paying for a fancy GUI for a server you cannot mod.
Take a little time and learn how to run a real server, and your wallet will thank me.
Having used Realms for two months, I can confidently say that it was a poor experience.
I am writing this in hopes that aspiring server owners don't make the same mistakes I did. There are several elements to Realms that are not necessarily presented upfront.
On my new server there I zero downtime, so I can join instantly.