KTM top boxes

Anybody tried fitting a 1150GSA top box to the KTM adv.
Now it's been a couple of years simce i had my GSA but i'm sure you can fit a normal helmet in it,this I cant do with the hepco box.So as i have been without my top box for nigh on 9 weeks due to various issues , soon as i get me new one back under warrenty it's gunna go,so may look at doing the above or other options.
Anyone using something other than the hepco box or tried anything else?
Pic of me old tin can(which I aint got!)

I'm using a Givi which came with the bike.

I managed to get the two std end cans inside as the bike came with Akro's.

It looks big enough for a helmet.

I might just look at these as I see they have the ktm

http://www.cajasahel.com/readnews.php?NewsID=42

But have not seen pictures yet.