Hello
I would highly advice to get ap 103
AP 93 just can use one band at one time i mean he use 5ghz or 2.4ghz, but not both at the same time
AP 103 are dual band dual radio which let them use 5ghz and 2.4ghz at the same time.
The price of the AP 93 and the AP 103 is the same, so you get much better AP for the same price.
As you can see here
https://www.arubanetworks.com/products/access-points
Ap93 was removed already.
Now the requirements for the AP 103 is 6.4 firmware on your controller
You can check that here
https://www.arubanetworks.com/products/access-points/103-series/
Go and look for the minimum verision and you will see you need 6.4
Now this is important so pay attention
If your controller is a 3200 then you NEED to buy a memory upgrade kit
without it you just can upgrade your 3200 controller to 6.1.x
If you get the memory kit, you wil be able to upgrade it to 6.4.x code.
if you got a 3200MX then you dont need the memory kit.
So check which model you got.
Why wont you be able to upgrade the controller?
Is this a local controller managed by a master controlller on another country? (this scenario happens often here to some of our clients in our country)
As an aside note, if you consider getting the ap 103, it would be useful a site survey, 2.4ghz can reach further than 5ghz, and you will not want 5ghz isles. There are a lot of things to take in considerration, this is just not so simple :)
Cheers
Carlos