DSF

Been out of the Dye sub market for a few years now
but looking to return, I have a friend that prints wide
format polyester material for football/rugby shirts.
My question is will the paper he prints on to be OK
for other subli work ie: Mugs Coasters ect.. if so it saves
me buying a subli printer .....
Thanks in Advance..

Maybe OK, but possibly not - the only way to be sure is to do a test print. If he is specialising in fabric then he could be using paper less suitable for hard substrates.

If it is not suitable, can you supply your own paper to your friend?

Most likely it will be fine, we use the same paper for our wide format fabric work, and for our mugs and coasters. But, in saying that, you can get paper which works better for fabrics in terms of how it releases the ink, but also has a slight adhesive/tackyness to help cling to the fabrics as it passes through the rotary press (saving having to use sprays) this may not work so well on hard substrates.
It's not gonna take much for you to find out though.

You'll also want to check the resolution he's printing it in case it's not high enough for your blanks.

... and the amount of ink he is laying down.