Cinders,
No, you don't need to supply a checking or savings account number to PayPal unless you want them to deposit your funds directly into checking or savings. You do need to supply them a credit card number to receive your funds by check.(I used my Fatshoe card)
As far as comparing cashout values, you need to consider PayPal charges you $1.50 to issue a check. So if CR is the only program you plan on using PayPal for, you should subtract $1.50 from what you will receive(i.e. 2000 points for $8.50, 5000 points for $23.50, etc), so it may be cheaper to cashout for WC's(5300 points for $25). I hope that makes sense. If you plan on using PayPal for other programs(or wait until after multiple cashouts before requesting a check from PayPal) then the $1.50 would be less of an effect.
I hope that answers your questions.
