the nicest thing about the Pi is no fans to draw in dust.
it is very small and quite, I use a wireless keyboard trackpad so I can make small jogs while standing over the machine which helps me.
apart from Easel I also have used CNCjs (browser based) Chilipeppr (browser based) Bcnc (python) Universal-G-Code-Sender (java =no visualizer but can handle huge g-code files).
Of these I use Easel then UGS and lastly Bcnc, I found that browser based programs could not handle long g-code files due to size limits with browser security. and when I use the laser some files get very large.
I can say that using the Pi has been the best. and if it ever fails it is just $35.00 to change or upgrade.