Refunding S2 MK2 for XDJ R1 or AERO?

Hey there,

I've been bedroom-djing for about 6 month now. I started with a DDJ SX (not mine) and Serato and after christmas finally had enough money in my pocket to afford my own controller so I went to get the S2 MK2. Since then I had a lot of fun with it, learned the ups and downs of Traktor and at least in the last 20 days NI did not create a good and reliable image of it's products to me.
I expected there would still be some problems with the MK2 and my iPad, but since the iPad version does support Meta-Data-Sync now and Traktor doesn't, that won't help anymore. Also the S2 did not prove to be stable either. I had a lot of crashes on the controller, even one on the controller+TraktorPro.

I am allowed to refurbish the S2 for the full price within 30 days after purchasing, so I can overthink my investment.

When I had he DDJ SX the hardware was just great! It was solid. But the more I worked with software the less I liked the idea of it, so I think what I want are CDJs or - since my budget is low - one of the little browers: XDJ R1 or Aearo.

To cut a long story short: Which one should I go for? XDJ R1 or Aero? Especially since the Aero lately got an updated iPad software which I haven't found a lot of information on. Is it like the R1 one now? Is the only difference the CDs and the file-transfer?

Thanks a lot in advance and sorry for my bad english. Greetings from Germany.