Taking the UK as a whole, the Holiday Inn / HI Express / Crowne Plaza grouping via Priority Club is EASILY the biggest chain in a loyalty scheme.

It is worth noting you can also buy PC points very cheaply using something called the 'cash and points and cancel' trick (see the PC FT board) which means that you will NEVER pay more than $150 for a HI / HI Express or Crowne Plaza, because you can buy the necessary points for that amount.

You can transfer Amex MR points to PC, as well as Chase Sapphire - that is 100k points (4 nights) just for getting the Chase Sapphire card. You can also get a good deal with the PC card https://www.mychasecreditcards.com/5...RRIDE_CELL=PQT. Amex or Chase Sapphire points count towards status, so you will be instant Plat at the same time.

I recommend studying this blog http://thepointsguy.com/ which dedicates a lot of space to credit card sign up bonuses. Basically, you don't need to do ANY spend on a credit card for your goal, you simply need to take out (between you and your partner) enough cards with fat sign on bonuses. Look here http://thepointsguy.com/2011/06/it-n...ire-preferred/ and http://thepointsguy.com/2011/05/amaz...ar-fee-waived/ for a start.