I only see the new model 9430 with the new-style pump listed at tunze.com. The price point is higher than the older models, at least according to my recollection. (The phat new pump accounts for the difference. Similar to the Stream 3 pump, a mag-lev bearing, dead-silent operation are at least a couple of the pro's for the new pump.)
If you're looking at the older models make sure they are actually available vs just being listed. I've seen quite a few online listings claiming "in stock" that were not really in stock. I think they've been out of the channel for a while at this point...some of them were only "in stock" as a drop ship in the first place. The older models had both AC and DC pumps available, but both were conventional style pumps.