In short you are correct, you can swap to the uni bar and it will fly fine. I find that with any straight four line kite you can fairly much use any straight four line bar as long as the width of bar is appropriate for the size kite.
I've had the 12m Trigger with the new Uni Bar for a week or two now and I'm absolutely loving it!
Admittedly I'm only a beginner who's just happy mowing the grass, though I'm getting upwind no problem so at least there's no more walk of shame 
So this is purely from the perspective of a beginner who was looking for a forgiving kite with a simple clean bar (my other bar has below bar depower and I find it really finicky to use 
).
The bar is bloody great! So simple to use and I'm not constantly either trying to get the depower strap to "catch" in my below bar cleat or else always double checking to make sure I grab the correct above bar strap/colour when on my mates 12. The only drawbacks I've found so far is that the grip on the bar is quite hard and as a beginner I tend to hold on for dear life on occasion (so after a long session my hands are a bit sore). Also the line colours for the outside lines are a bit too similar (blue/white and black/white). In saying that the pigtails are yellow and blue, so easily distinguishable when actually connecting them to the kite. Being the symmetrical loving guy that I am it would have been nice for the line colours to match all the way from the bar to the kite though (i.e. yellow all the way from the bar to the kite, including connection lines on kite and blue all the way on the other side).
In saying this, I find the above really minor and with the pigtails being yellow and blue it does make it difficult to stuff up, even for a beginner. I'm sure my hands will adjust and as I improve I won't need to grip onto the bar so much/so hard!
I've had it out in 15-22kn so far (I'm 75kegs) and its super stable and smooth with its power delivery. Compared to my limited time on other kites its nice and predictable through the wind window and I actually feel in control all the time! As a beginner this is great as I'm not constantly worried about diving it too hard/being hit by a gust with a resulting face plant and nose to backside enema.
I've been on other 12's and when the wind gets up to 20+ I'd find I was well over powered and would really struggle getting upwind (I seemed to get pulled off my edge all the time). In similar winds on the Trigger I'm having no problem holding an edge and going up wind like a truck (well to me it feels like a truck but to all you experienced guys its probably more along the lines of a mini 
).
So all in all a great kite that I'm really enjoying. It does seem as if its really helped me improve over my last few sessions, its so forgiving it seems to just want to keep me on the board! Though this may have something to do with riding a Monk Forever 132 x 41 as well 
So if you're a beginner like me umming and ahhhing about what to get, then give the Trigger a demo if you can! I took a punt and bought mine site unseen, I couldn't find somewhere in Vic to demo one and they were only recently hitting Australian shores when I ordered mine. I'm having an absolute ball on it and will now be relegating my 9 to the super windy days only (if I can stop myself from replacing this with a 9m Trigger as well that is)! Gotta love a decent session where you come back to shore with your smile muscles hurting from the ear to ear grin plastered to your face for hours on end
If only this crap rain would piss off so I could get back out there I think I've developed an addiction...
Cheers,
bakz
