Greenwood's price went up 20p after a tap in and Brewster price went up 20p (ish) after scoring 2 goals against Tranmere.
Both managers have said Greenwood and Brewster have a first team roles this season which suggests they're both good enough to cut it at the top. Obviously Liverpool are challenging for the league and champions league again whilst Greenwood could get a decent run in the Europa league.
There seems to be more value in Brewster with a 52p difference and from watching the way Klopp coaches his young players ( TAA,Gomez,Robertson) this leads me to believe he'll bring the best out in Brewster. Klopp also turned Lewonsdowski into the worlds best striker after signing him from a Polish club so lets not forget about that. You can't go wrong with either in my opinion but i'd be holding for the long term on Greenwood or Brewster.