4x Riteks with a 1x burner

[cactus]

I normally get my Riteks from Rima.com and get nailed with a huge shipping cost at the border (I live in Canada). A new store near us only sells the 4x Riteks and its actually cheaper than ordering from the U.S. I didn't want to order a bunch if they won't work in my 1x Pioneer 1A04. Can I still burn at a lower speed with higher speed DVD-Rs? Thanks!