Darren,
All Prints are susceptible to fading given enough time. Even Screen-Printed.
The affecting factors being the lighting used, the inks used, placement of the artwork (aka - direct sunlight/UV exposure), etc...
When artwork is printed using today's newer professional inkjets, inks and materials, they are very color-fast and resistant to fading.
The correct inks have UV protection and the correct over-laminates, if used, have UV protection as well.
To answer the question directly, I have never personally purchased a Marquee from GoG or Emd but I do know that the materials they use are the correct ones.
I'd be glad to answer any other questions you have.
My email is john@basementarcadegrafx.com or call me at 517.8512.4286
And Yes, I do have my own arcade printing business but I'm happy to help no matter where you purchase your artwork printing from.
John