There are others offering more for less with a better customer service attitude.

I was impressed with Zenith when I started using it in 2008, but always felt as though there was a disconnect between the parent company (in India) and us U.S.-based users. Since Continuum purchased the RMM side from Zenith InfoTech, I have been very pleased with the changes they have made and the new features they have implemented. Not all of the changes have been favorable in my opinion, but the vast majority has been great.

From a technical standpoint, Continuum has a very short learning curve. I find it very intuitive and very powerful without a lot of tweaks and adjustments. Once you login to your portal, you create a new user, create agents for servers and PCs, and then download and install them.

What makes Continuum worth the larger than average price tag is the human factor. I leverage their highest-level of agent on servers, which means I have a team of trained personnel sitting in a NOC overseas waiting to address alerts generated on protected servers as they occur. Also, at this level I can create work for the NOC to do after hours such as an off-line Exchange database defrag; this is huge. Sure, other agents average around a $1 a system, but guess what; you have to defrag that Exchange database at 2 AM or trust a script to do it for you and hope everything works when you wake up. I can even purchase a US-based help desk program for up to 24 hour support for end-users and they will answer the phone as my company.
Continuum listens to their partners and a lot of the features they add (each month mind you) are directly correlated to what partners are asking for. Yes, they are a lot more expensive than others out there, but having tried a few of them, I can honestly say that I now understand what I am paying for and will gladly pay it for years to come.

Since Continumm split from Zenith Infotech, there has been impressive movement to make things better such as updates to the portal, additions to scripting, the Mac agent, and much more coming. I was not a huge fan of Zenith RMM, but it seems that Michael George and his team are doing the right things to improve things. I will say the support seems to be improving since beginning of the year. There is also better communication to partners.

For the price you pay, you get a lot. I also use GFI which seems to be a another RMM tool creeping up for MSPs, but they still have many features lacking still. GFI is working hard, but I just feel Continuum is ahead right now. Add the fact I can add helpdesk and included NOC, it's hard to beat the big RMM companies.