KLM offers higher compensation than EU 261 stipulates if you agree to take it as a (non-refundable) voucher rather than cash.
I always take the voucher option as I spend more than enough on AFKL flights anyway that the extra value is easily used, but if you're not an AFKL frequent flyer the cash option may be worth more to you. AFKL vouchers must be used with AFKL.