Is it still worth buying N4 and N10?

Hi,

I'm from New Zealand and I'm looking forward to get some android devices this time.

I'm currently using iPad 4 and iPhone 5. I saw the price of N4 and 10 has been dropping here(in NZ) so I'm quite temping to get both.

the price of 16gb N4 and N10 is $335 NZD and $530 NZD respectively.I don't think it's a bad deal but I'm just wondering how these devices would handle the next gen of android.

and I want to know if the ecosystem for 10" tablets has been improved since the beginning of this year. Actually I tried both devices around March this year but I was quite disappointed by a lack of tablet optimized apps.

Please share your experience with N10 and tell me what you think about getting these devices at this point.

One more question is that... Is it a good idea to get a Xperia Z1 over N4 or N5? There is a huge discount for Xperia Z1 so I don't want to miss this chance.. What do you think guys?