I have been mudding for years. I have also been building on a mud for a few years. While our server was down for a week for maintenance I figured that I would finally give ROD a shot and see what all the hoopla was about. Honestly, I was not that impressed.
ROD has a ton of rooms and an amazing amount of players. However, ROD does not do much for lower levels. I did not find the Imms very helpful at all. In fact, I don't believe any question I ever submitted was answered by one. Other problems I found:
-Severe lag. ROD is one of the slowest MUDs I have ever seen. Should you have zmud and like to use speedwalk, forget it. Realms has a continuous, permanent lag which becomes increasingly frustrating.
-Corpses. Corpses disappear after 30 minutes in RL. Should you be so unfortunate as to die at lvls 2 or 3, before you've learned where you are going, you are most likely to be unable to retrieve your corpse. And to all those who spammed the reviews with how helpful everyone is, I would ask you why newbies get assaulted with unbelievable hardships when they should be enjoying their first taste of the mud.
There are many out there who truly love Realms. And it is certainly a very competent mud. If your goal is to see a ton of people when you do a 'who', then Realms is for you. If you goal is to play an enjoyable mud with more features and kinder to those in their first mudding experience, I think you can do better than Realms.