Hi Wbasset:
I´m on same boat than you. I mean that I like that a lightgun has Perfect accuracy, as you say.
In my case, the Accuracy is PERFECT, I show it on my youtube videos.
About the Lag: I know that it bothers, but ALL THE LIGHTGUNS until this date, have something like 15-20 ms of lag.
Wiimote pointer has same lag than Topgun and same lag than a Guncon 1,2,3, and the same lag than the lightguns found in arcades. I have test it by myself, not just a theory.
Doesn´t matter if the lightgun is InfraRed or if it is the typical "old Flashing white lightgun"
As you say, in police trainer "experienced levels", the targets go like crazy and it is pretty hard to shoot it.
I´m not a programmer but I notice that the cursor tracks FASTER under windows that under MAME.
My trick is that I try to imagine that I have a pistol which shoot at around 350 meters for second, not an assault rifle wich shoots at supersonic bullets.
The problem is that when LCD TOP GUN it goes Wireless (Rf Topgun) It seems you can add a 8 ms more of lag.
So: 15/20ms that all lightguns have + 5/8 more because Wireless + mame tracks slighty slow than windows = Not recommende
For gamers
I would recommend it for "parents and kids" because design is cool and buttons are "Soft and easy"
Now I´m going to read and reply detailed what you said.
The gun itself is an XBox gun that they modded. So that's why the same features aren't there that the TopGun has. Which that gun was a mod of a PS2 gun which already had the laser, recoil and other features. So it makes sense that this new gun doesn't have those features because they don't really make their own guns, rather modify others.
"LCD TOP GUN" was a Beretta modified (with laser pointer), after EMS released it, it seems other chinese manufacturer copied it only for Playstation 2. But the first model was for EMS
"RF TOPGUN" doesn´t exist on Xbox (neither PS2) It exists a model wich is very similar and was compatible with 100HZ Tv. I know wich one are you imagining.
There is not any lightgun for Xbox has big buttons on sides (called A & B) "A button" was the Trigger on Xbox
Accuracy is a big concern of mine. Blob shooting is okay in some games, but others do require precise tracking. It's those games that I found issues with my TopGun experience.
I must admit that lag annoys me, but Accuracy on topgun is perfect, Here are my youtube videos of Topgun, you can see accuracy.
http://www.youtube.com/user/aljupiHopefully they will be quicker at getting a software update out there that improves the accuracy and distance than they did with the first TopGun. I really really want to like their products and if they can get the wireless tech working I have plans for some pretty cool mods.
But How? The lag is there, 45 updates for second is poor for me.
It is tech issue, it doubt that a driver could fix aa normal tech lag. (Lightguns have lag and wireless devices always has slightgy more lag than a corded device)
If they can't, well then I will be going with Dave's Sonic design. I wish his was wireless, but I can live with that if the performance is top notch.
It is the first time I hear a "Sonic Gun". Maybe performance could be FASTER than Infrared, I imagine that a "Lightgun´s cam" can not read IR at the speed of a bullet
Let me ask this... Is there any type of advanced calibration with the RF TopGuns that may help? I know the TopGun II improved on that some,
No, it uses THE SAME, than the TOPGUN2
and although I only have a first gen TopGun myself, I found that putting the sensor bars above and below the screen instead of to the right and left of the screen improved not only my accuracy but also the distance I need to stand back. Have you tried that?
Yes, I tried, but even that way, a Topgun1 can play half meter closer.
The distance is not a problem for me

I like to play a natural distance from screen. Not a 1,5 meters for a 40 "Inch ".
The update time though seems like it will cause lag
No, the update time, makes the cursor "Shaky" (only while tracking)
I am still waiting for something that I can do my custom gun mods with! Hopefully EMS will give you some sort of solution to the problems you noted, and hopefully it won't take two years this time! 
If not, I won't be waiting two years, I'll be going with Dave's solution.
Well, I do not know how are the lightguns you have bought, but LCD top gun1 with a good driver, are the best, I have the other lightguns released in the past for PC and LCD TOP GUN1 is a jewel for me.
Anyway I hope competition with Sonic Gun system, I like Lightguns are going for better not for worse.
Regards "RFTOPGUN": I like that EMS tried to do it Wireless, it was a nice try from his side. I wish them good luck
Best Regards