Touch Monitor Size - Any Consensus?

I am beginning to shop around for parts for my mill and I'd like a nice "big" touchscreen but no idea what constitutes big enough or too big.
As a reference, Tormach's screen is 17'', I think and it does look a tad small. I'd like to operate sliders fairly easily and not miss buttons. 
(I'll be using either ProbeBasic or QTDragon-HD, still undecided)

I was thinking to go with 24'' but maybe there's a point where you also have to move your hand too far to reach different parts of the screen? So, maybe 21.5-22'' is a happy medium?

What are you guys using? 
 

17" for the mill and a little 10" jobby for the lathe. Then again I'm strapped for space.
Honestly I prefer real switches & knobs. Call me a hi-tech luddite

I have 15.6" which is a tad small. 17" would be my choice. Go too big and you have to move your hand too far between elements. Thats what I found with 24" on my first machine using gmocappy

Hi Rod,
Thanks for weighing in:)
It might very well be an older post of yours that got lodged somewhere in the back of my mind as to the larger movements larger screens would need.
I'll strike 24'' off the list.

I tend to think, just from looking at screen grabs, that ProbeBasic might like a bit more real estate whereas QTDragon might still look alright on a slightly smaller screen.

My eyes aren't what they used to be which is another reason, I am willing to aim a bit bigger and I think 17 might be just a wee bit too little for my liking. Maybe 19-22'', then.

I would love me some "real switches" but I know LCNC in itself will be a big enough rabbit hole to start with.
I already have a folder with snaps of consoles for inspiration, but I am trying not to look at it. Trying to stay simple for now with a touchscreen and a keyboard.

This is also my first CNC so once I have run it for a while, I'd have a much, much better idea of whether I wanna take on a panel project and what I would actually like to have on it.

the new GUI's you are considering are more touch friendly than Gmocappy which has a lot of tabs you need to open all the time . eg jogging.
QT dragon has a lot flatter UI but still has plenty of tabs but the jogging controls are always exposed.

rodw wrote:

the new GUI's you are considering are more touch friendly than Gmocappy which has a lot of tabs you need to open all the time . eg jogging.
QT dragon has a lot flatter UI but still has plenty of tabs but the jogging controls are always exposed.

Yeah, I just had another look around and found a very short video of Probe Basic being demo'ed with touch on a 21.5'' screen which actually looks like a nice size for me. Still a bit "far" from end to end, but I like the bigger text, icons and sliders. 
I'll be buying the screen secondhand, so what's available will also be a factor.

Screen size and resolution goes hand in hand.
My 17-inch touch for the milling machine use 1280x720 and I run the low-res qtdragon there and it works great, buttons are good size and sliders too.
On the lathe the 24-inch touch screen use gmoccapy in 1920x1080 and most things are ok size but there are sliders that are a bit hard to hit because they are so small. And the size is too large, need to move the hand and arm for many things.
The screen resolution (virtual screen resolution?) can be set and for example a 15.6-inch laptop-ish touch screen with 1920x1080 resolution can be set to 1280x720 (virtual?) resolution and have all the graphical elements come out in a more reasonable size.

Hakan wrote:

Screen size and resolution goes hand in hand.
My 17-inch touch for the milling machine use 1280x720 and I run the low-res qtdragon there and it works great, buttons are good size and sliders too.
On the lathe the 24-inch touch screen use gmoccapy in 1920x1080 and most things are ok size but there are sliders that are a bit hard to hit because they are so small. And the size is too large, need to move the hand and arm for many things.
The screen resolution (virtual screen resolution?) can be set and for example a 15.6-inch laptop-ish touch screen with 1920x1080 resolution can be set to 1280x720 (virtual?) resolution and have all the graphical elements come out in a more reasonable size.

Hi Hakan, 
Thanks for those examples and the res vs. size is a good point!
I think I just have to make sure I get a 1920x1080 screen as I read somewhere that Probe Basic needs that. And then if I go with another screenset I can run the screen at a lower res if that helps navigation. 
Also, thanks for confirming that 24'' gets too large.

If you had a choice between a 19'' and 21.5'' what would you think would suit you best?