displayPort to HDTV extension

I have 10 foot Cable Matters Gold Plated DisplayPort to HDTV Cable, that I bought last November. I use it to hook up my laptop to TVs for video presentations on the road.

I sometimes need an extra 10 feet.

My questions:
1. ) Would it be OK to get a High Speed HDMI Extension Cable? Or would I experience degradation?
2. ) I have read that display port can handle anything from 1080p to 4K.
a. ) Is this true?
b. ) Would this be a reason for it to be fine to hook a high speed HDMI extension?

EDIT -- Just thought... Would it be best to use a DisplayPort extension?

So far I have only encountered 1080p, but could conceivably run into 4K... so the answer might be that I am fine for 1080p, but not 4K.

Thanks

 

Thanks for the response. What length cable are you using?

 

hmm.... I'm running 25. I might just have to try it and see... unless anyone else can add some input.