There isn't any real evidence that the new CPU is better for these devices. I don't think anyone has compared the two versions for the Aura H2O Edition 2 side-by-side or even had both available to them. The people getting the Clara HD have been saying they seem fast. But, is that just the CPU or something about the overall design?
If you are worried about how long Kobo will support the older version of the device, don't. Kobo are still putting out firmware for all three versions of the Touch. They have skipped a few versions for different devices over the years, but that is mainly while concentrating on a new device.
As to the likelihood of sending it back and getting one of the newer devices, it probably depends on where you got it. Most places would buy a batch of them and get a new batch when they are running out. Each batch would be only one version. And they would try to get rid of the older one first. To me that would make it unlikely that if you were getting the original version from a shop that the next day they would have the later version.
|