I've seen many of the kits that have been available in the U.S.
Moss Lo-Pros are the best aftermarket headlight out there.
They light up the road better than Hella E-Codes or AAC. In fact, the flush mount lights are all a compromise in performance as the light can't get past the fenders when they are sunk in.
Brain Storm Euro-crappies and the Mid-Ten are poor build quality and a waste of money IMHO.
Brain Storm Lo-Pros don't measure up to the build quality and light output of the Moss kit.
The best bang for the buck is Hella 7" E-Codes. They are almost as good as the Moss lights but you retain the factory look.
The best light output with a custom look is the Moss kit.
If you are absolutely dead set on flush mount the AAC kit is the best but you REALLY pay for it. It actually uses the same lights as the Moss but as I mentioned, the light output is compromised purely because of it's design.
Also keep in mind, No kit is perfect. The Moss kit is close but still not OEM quality. Two local guys have said the AAC kit they installed had fitment issues. The others I mentioned basically suck and should be avoided.
Note: I didn't mention Hyashis, KG Works or other kits as they are not readily available in the U.S. and I have no experience with anything but the U.S. Kits.