Simplifying my answer here......
There is a 23-inch Touchscreen Lenovo Core i5 with 8Gb of Ram on Amazon right now for £500, that will easily run the current Roon app
So the questions for Control:15 owners are
a) How much will it cost to upgrade my Control:15 to run a version of the Roon app allowing for all the items below [and probably some I haven't considered]
* an SSD Drive
* a RAM upgrade
* an upgrade to the Graphics Processor and Chipset to allow it to run OpenGL 3.0, which is largely what Roon uses to achieve its graphical speed
* a new OS Licence
* the Labour Costs of removing the current components and replacing with the items above
* the installation and testing with the new OS and modified Roon app to make sure everything is hunky dory
b) Is the total cost of the above likely to be less than the above £500, after factoring in all handling and shipping charges etc., especially when manhours are usually the most costly part of such upgrades and testing
c) even after all of the above is done, how comparable will the UI EXPERIENCE be with the modified Roon app on IMHO a below par Resistive screen ... by comparison to running the optimal Roon app on a modern Capacitive screen with much faster Processor and RAM??
I could ask the same series of questions about how the costs of upgrading say an MD600 to meet the needs of the Roon app... and how those costs compare to the £250 price of a decent QNAP 251... and more importantly, after upgrading how will the actual User Experience compare??
In simple terms, there's a very good reason why most people and Companies just go out and buy new Computers [never mind Toasters, Coffee Makers and Phones], rather than just continually upgrading their older "devices"... and the reason is that it simply costs too much to upgrade old kit... and in the end, the User Experience is compromised anyway, as in general New Kit will always Outperform Old Kit [even after Upgrades]