of your journey, I'd opt for a paper NR ticket, unless the Oyster
'touch-in/out' convenience is very important to you.

Most operators give discounts when they fail to meet performance
levels - I've had 5% my monthly 'Period Travelcard' every month for a
long time. This is enough to keep me buying from a NR station.

What if you renew at a shared TOC station on a line that gives charter
discounts? Do they issue paper or Oysters?
http://www.oystercard.com/buy_toc.php