Is laptop for cnc is a bad choice?

Guys , I recently found an older but still new laptop at my computer store that has windows 7, an IBM ThinkPad
. It has the usual dual core proc and 4 gigs of ram.
I recently heard laptops were not a good choice for running a cnc router . My intentions are to purchace a 4x4 Pro version from famaga next year . I am going to build the electronics myself, and use motion control board suited for UCCNC that uses a USB or Ethernet port .

I’m assuming the concern with using a laptop is sharing the video card with other memory etc .
I am not going to use this laptop for rendering , just for running the cnc . I prefer the laptop, as when I had my laser running , the desktop , keyboard mouse and monitor used a lot of real estate . I’d love to just have an arm connected to the side of the cnc holding a laptop instead .
Any thoughts or bad experiences using a laptop?

The latency is probably horrible, for the reasons you named.
Mark

Take a live Linuxcnc DVD or USB drive to the store and see if they will let you boot it up on it and test the latency a bit. If it can do decent Latency numbers, your good to go.