Here's something I've been thinking about over the past few days that I don't have an answer to: If you've tried but haven't succeeded implementing VDI within your company, do you think going to a DaaS environment will be easier or harder? I can see both sides of it.
My first instinct is that DaaS would be easier. After all, you're just subscribing to the VDI as a service, and you don't have to worry about server sizing and storage and IOPS and all that stuff. On the other hand, many (if not most) VDI projects fail not because of the "VDI-ness" of them, but because people try to do too much at once. (i.e. they try to go from traditional persistent desktops to VDI with shared images with all apps virtualized, etc.)
And while DaaS providers do do the heavy lifting when it comes to the actual design and building of the VDI, the mere fact that you're buying these desktops as a service introduces all sorts of new complexities that you wouldn't have if you built VDI on your own.
For example, what if your DaaS provider takes a cookie-cutter approach to their offering? Then you have to try to shoe-horn your desktop needs into their pre-built environment. You also have to figure out how to extend your user authentication to their system, and you have to deal with the split-role of administration. (What happens if your DaaS provider handles the OS patching, but one of those patches breaks your apps? Can you roll back? Whose job is that?)
And then of course there's the fact that if your DaaS goes down, you're calling a phone support line to get it back up and running, and you have to deal with the blame game to hunt down the source of the problem.
Also as many have pointed out in comments here over the past few months, DaaS means your desktops are in the cloud, but if your data and Windows business app back-ends are in your datacenter, how do you get those to talk to each other? What does that mean for performance, and how do you set up the security? Also now you have to deal with two sets of everything (internet connections, firewalls, power, etc.)—one set on your site and one at the providers.
So what do you think? Is DaaS "easier" than VDI? Or is it more difficult? If you haven't been able to make VDI work, then why do you think that DaaS will magically work for you?