Dave - was it easy to cancel your pre-order? I'll use this to hold it, but probably cancel if I can easily find one in stores.
No - it was not easy to cancel my pre-order for the R5-D4, but on the upside it might land you the R5-D4 you still need...
I had grabbed an R5-D4 from the local store and then went online to cancel the order. There was no way to do it online so I had to send an e-mail, which seemed to annoy the customer service team. They sent a confusing e-mail and then followed up a day later and said they couldn't cancel the order because it was already boxed and ready to ship, even though it didn't ship for another three days.
At the very least you should be able to return it to a store if you don't want it, but then you'll be out the shipping/handling fees.