Still waiting on the NES clones to come down myself. I've been thinking of getting a custom cart of the hacked zapper games that run on a lcd tv. Seems like it'd be better if a few of us got a small run made of them but I question the morality of that. I wish the guys who did the hack would do that.
I've tested the hacked lightgun games quite a bit. A big drawback is needing to buy a 3rd party lightgun. I got the Tomee Zapp gun, which is smaller than a Zapper, with a cheap feeling trigger and a very short cord.
As for the LCD hacks' functionality, it has worked well for me, as long as the target is at least as big as a duck. I can't seem to reliably target anything smaller, such as clay pigeons in the distance. The Duck shooting part of Duck Hunt, Wild Guns, and Hogan's Alley work the best. Some of Barker Bill's mini games work well and others don't, again seemingly based upon target size. I suppose part of it could be the latency of my TV, although I can't remember those numbers off the top of my head.
It is pretty cool to be able to play the arcade version of Duck Hunt at home on an LCD, although it didn't seem to work for me as well as regular Duck Hunt.
Also, a friend of mine recently got a CRT, so I brought my NES over and we played through all the light gun games. I'm sad to say that the selection is really poor. Nothing ever got better than Duck Hunt. Freedom Force and To The Earth had a lot of potential, but just ended up being repetitive and boring. Gumshoe was fun for about 5 minutes. Baby boomer needed a lot more polish and design work to make the levels interesting.