Fair warning, I am going to be truthful and go by exactly how I perceived it, yes its subjective.
Tweeters:
ScanSpeak Illuminator (small)
- The Illuminators were very impressive for a 3/4" tweeter. They played down low to 2.2khz with no noticeable distortion. We did not play these lower because I was afraid to damage them. But for $400+ Tweeters I was not overly impressed. I wish the top end would extend a bit further. These werent excessively laid back but they were a little lacking. These would be perfect for anyone who enjoys that warm fulfilling sound. These placed 3rd for me.
Morel MDT12 (didn't have time to play with these)
No dice!
Hybrid Audio L1Pro
- These placed 2nd on my list. They played low down to 1.5khz. The top end was really good. We listened to the Mumbai Theme and the strings sounded great along with that triangle on the left side of stage, sounded very real. But lost points in clarity that triangle wasnt as focused as the ADI tweeters made them.
Hybrid Audio L1v2
These did all around poor in the home audio realm. As Scott said these are strictly for a 4-way setup(sub,midb,midr,tw). You really cannot use these below 3.5khz. It had no fullness, lack of clarity, and really had to feed them power to hear them. Now when listening to these in the car, they perform well! It sounds like a completely different speaker. Its strange how that works. I guess with all the reflections in the car they dont need as much power and the sparkle better. but that 3.5khz comes to play in the car as long as you had a decent mid to pair with. On a side note, these performed soo poorly in the Home Audio but great in the car leads me to wonder if the L1 Pro performs terribly in the car, id imagine they would tear a head off! But I wont know until I try them in the car.
Tweeter X
There was nothing impressive about this tweeter at all. These tweeters had very little top end to me, and off axis even worst! Instruments sounded artificial, and vocals were hollow. They seriously demand tuning. These tweeters would be the kind that come in a mediocre component set. I cannot talk too much about this tweeter, I was asked not to for the moment.
Critical Mass T1-A (there was an issue with one of these so we didn't use them)
Thats pretty funny, for an overpriced tweeter made to market. They cant even make them right

just kidding, we dont know why this one wasnt working, something could have happened in shipping.
ADI XBL Ceramic tweeter from Dan Wiggins
Honestly these were my favorite! I really loved everything about these. These sounded better crossed at 1.5khz than 2.5khz. They love to play low, and they play plenty full too. these really disperse wide and can fill up a room. Off axis is really good, i suspect its because of that plastic lens on it. These had a unique dryness to the sound that made pianos, flutes, clarinats, bells sound solid, solid as in it didnt have any washed awayness, it had plenty of decay for those metal instruments. Now I dont know who(OEM) will pick these up but I hope they dont charge too much for them! But as great as these sound its going to be hard for them not to! side note: they sound extremely similar to the Tang Band version. The only difference I could really tell was the low end was significantly improved. These ADI's are happier playing lower.
I will talk about the fullranges a bit later.