Naim Nait XS is a simply wonderful amp - and will go very well with the Gibbons. I do not believe it gives much if anything up to the Supernait, and in fact, getting the DAC out of the box may actually provide a slightly "cleaner" sound in the XS. The Exposure will not sound better than either Naim, but will sound different as described above.
I put listening to an XS fed by an older very high end Naim CD player and played through Naim floor standing speakers in my top ten listening sessions of all time. It just really sounded closer to live music to me than I am used to hearing - including sessions with some much more expensive and carefully set up gear.
In the end, I say soundstage schmoundstage. If the sound of the Naim grabs you, then relax and enjoy what pleasures the it has to offer. I agree with Dbarger, Naim really does offer a "third approach" to music reproduction, one I happen to like a lot.
I put listening to an XS fed by an older very high end Naim CD player and played through Naim floor standing speakers in my top ten listening sessions of all time. It just really sounded closer to live music to me than I am used to hearing - including sessions with some much more expensive and carefully set up gear.
In the end, I say soundstage schmoundstage. If the sound of the Naim grabs you, then relax and enjoy what pleasures the it has to offer. I agree with Dbarger, Naim really does offer a "third approach" to music reproduction, one I happen to like a lot.