Above you can see some of the most popular, and well regarded compact neodymium and large format chambered tweets around.
I didn't have a chance to perform in depth objective measurements, but I did have a chance to listen quite extensively to each one and provide some brief subjective impressions.
Starting with the popular lpg 25nfa. This tweeter can be purchased from Solen, Madisound, or Meniscus audio for $65/pr. The sound is best described as very detailed, open, airy and light. One of the best tweeters I have heard in terms of upper end detail, dynamics, and space. The weakness is obviously in that it can't play as effortlessly at very high output levels, and low frequencies. I'd keep this tweeter crossed above 3khz for the best performance. Tends to get spitty and a tad harsh when driven too hard. Other than that very low coloration, and natural tonal quality.
Max Fidelity mfdt30neo. Can be purchased from Solen or Mensiscus for $110/pr. Almost as good top end extension, presence, and air as the lpg. The strength of this tweeter is really it's large 30mm dome, which gives it a higher efficiency and more effortless sound with low crossover points and high spl levels. The only weakness is the tweet can be a bit hissy sounding without proper equalization, and without a rear chamber it's lower end performance below 2.5khz or so isn't that great. All around a great choice for those that like the sound of the lpg, but wish for higher output levels, overall dynamics, and powerhandling.
Seas Lotus Reference silk dome. This tweeter can be bought at www.mobilesq.com for a cool $220/pr. The construction of this tweeter is beyond compare, with a solid aluminum chassis, grille, rear chamber, and very stiff, well built terminals. No cheap plastic used here, or easily breakable terminals. Now this is a tweeter that can be crossed over comfortably at 2khz, and has a pleasant, laid back sound. Overall dynamics are not quite as good as the Max-Fi, nor is the top end extension and detail up to par with the Lpg 25nfa. However, this tweeter has the capability to play lower than the others, and sound far more forgiving of bad recordings. The lower treble region, or upper midrange is also a shade more revealing and natural sounding. A solid choice for people seeking the best in build construction and quality, a low crossover point and better lower end treble, and doesn't care too much about the extreme top end detail/presence.
Last of the compact tweeters, the Rainbow Platinum silk dome. Only available as part of a 2-way component set costing $2500 msrp. Not an option for most people, but I would say without hesitation this is the finest compact dome I have ever heard. Build quality and low end treble performance are similar to the Lotus reference, but the sound is just smoother, more natural, and effortless. This tweeter is just so silky sounding, although it doesn't approach the top end detail of the Lpg or Max-Fi, it's just far more pleasing to listen to, especially with bad recordings. I'd sum this tweeter up as having great low end, and a very pleasing, silky smooth sound.
Large format ceramic magnet tweeters
The biggest difference with all the large tweeters is their low end capability. 1.5khz is not a problem for any of these tweets, and in general they are all capable of far greater detail in the lower treble, and higher, effortless spl levels. They are also without doubt much fuller sounding than the compact domes. All of these large domes are at the top of the class with regards to build quality and construction.
Starting with the Usher 9950c. $100/pr from Partsexpress. Although the cheapest tweeter of this group, it EASILY holds it's own against the much more expensive tweeters here. Very smooth sound, with a hint of sparkle and top end extension that is a little better than the Seas Millenium without the harshness of the 9900 Revelator. This would be a great tweet for those that love the sound of Dynaudio tweeters.
Seas Millenium. $320/pr from Madisound. The prettiest tweeter of the bunch in my opinion. The low end performance of this tweet is perhaps the best of all the tweeters. Sound is also the most laid back, forgiving, smooth, and "rich" sounding of all the tweeters. However, it may sound "shut-in" or too dull for some.
Scan-Speak revelator. $420/pr from Madisound. While this tweeter has perhaps the worst low end performance of all these tweeters, compared to most "regular" tweeters it's actually still quite good. Used properly, it may have one of the most detailed, and resolving top ends. However, on some recordings it may come off as too peaky or harsh sounding. I love the sound of guitars and metal instruments with this tweeter, but some poor quality recordings were just too fatiguing to listen to with this one.
Morel Supremo 130. $380/pr from Madisound. Not as full bodied as any of the other tweets, but it has the greatest amount of space and upper end presence and dynamics. Top end extension on this tweeter is great, giving it the best "sparkle" and air out of this group. It can sound a little too forward in the upper end for some people, but I actually liked the extra sense of space and top end detail it provided, especially on metal instruments. However, it doesn't quite sound as "natural" with many vocal recordings as the others. My only complaint is this tweeter had somewhat cheap, easily breakable terminals. So be careful when connecting and disconnecting.