I have 2 current machines running WinCNC and have owned 5 total. Very good and stable with the highest number of useable features available, especially for commercial users. There are so many built in features, I don't think there is a need for plugins. Do you have something in particular in mind?
Yes, you can adjust both feedrate and spindle speed on the fly.
They offer 2 pendant type controllers. One is a wired serial cable that is very programmable. The other is Bluetooth wireless that gives you access to all the screen features and buttons and has an mpg jog wheel. Also has display of machine and user coordinates. Multi level programmable to your needs.
I have used a webcam for positioning and diagnostics, but not on a day to day basis. WinCNC has an Opti-Scout option that will located registration marks and even stretch/skew the cut to match positioning of the graphics. Also cut DXF with cutter comp.
One of the best "pros' to WinCNC is their branded I/O products. They can provide OEM matching, opto isolated, top of the line breakouts with up to 30 inputs and 20 outputs. 6 channels of simultaneous motion approaching 100Kbits/sec to allow high resolution encoders. The best I've seen in PC control.
Disclaimer: I do not work for WinCNC, but I do buy their products, along with those from other control providers, as I retrofit CNC machine control for a living.
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