I have no problem paying the extra, but expect the item to arrive in good time, not 7 - 10 days after payment, otherwise what is the point.  I post the same day or next day after I receive payment, depending on time of payment and use click and send, and my items nearly always turn up in good time (the odd one arrives slow, but what can you do).  I don't see the sense of offering express if you don't intend to post asap or you are out of the zone.  If you are outside express zone, offer registered or click and send, at least they are recognised by paypal as a recommended form of postage for protection, and I don't mind waiting for them to arrive if I know what I am paying for.