If you trust ratings then King Of The Plains would be a good thing based purely on his rating compared with Sweet William,the latter is 4/6 compared with the former @ 11/4.
King Of The Plains is rated 84,SW 85 but due to the wfaa has to give 12lb.KOTPs Yarmouth form makes the ratings even more interesting as he was beaten just a head by a 3yo stablemate of the fav after rearing in the stalls,he gave the winner 5lbs that day,the winner is rated 96.
That form alone makes the issue of ratings questionable and would appear to make KOTP a "Handicap" snip,imo the fav has a good bit to find and 1st time blinds rarely improve a horse to the extent he needs.
At the prices and all considered I feel KOTP is worth a punt. ( One other angle is if the Premiership tip the fav,it carries a penalty)