Yamaha NS-1000M

I don't know about that. I do get a pretty solid image. Maybe not as pinpoint as other speakers, but pretty good still.

Imaging has more to do with time alignment then dome vs. cone and to a lesser extent, intensity. The one thing domes do, is that they increase the area of the sweetspot. That is why most tweeters are domes. Producing high frequencies off axis is difficult, especially outside of 30 degrees. By using a dome, the window is widened. With a normal speaker you can clearly distinguish when you move a foot or two to oneside of the sweetspot. The image begins to collapse.

Japosey,
You are right when you say that domes provide you with a wider sweet spot but you get a bigger sweet spot of lesser quality.
I built some speakers using Cabasse DOM 12 midranges.These sound superb but simply don't image, even when time aligned.I have spent hundreds of hours working with dome mids,crossovers,time alignment,different driver confgurations etc etc and gave up in frustration.The only way I could get them to image precisely is to use them in an Edgar mid horn which of course changes their dispersion pattern.I have used domes from Dynaudio and other less well known makers and they are all the same in this regard.
I have since had it explained to me that dome mids interacting with other drivers create phasing problems and this is why they don't work as they should in theory.
This is the sonic equivilent of sitting front row centre at the cinema.There is plenty off stuff going on but you keep shifting your head from side to side to try to take it all in, and what is dead in front is not quite in focus.
As for domes in general have you noticed how few manufacturers use them now?There is even a big move away from dome tweeters.Focal/JM lab and Accuton both have opted for cones and many others are now using ring radiators or ribbons.

JT

I can see how phase issues can be a problem. Yeah, JM Lab has used that inverted tweeter for awhile. I really enjoyed a pair that I had awhile back. If there was a perfect answer we wouldn't be having this discussion now. That's what makes this hobby so unique. As soon as you get used to one thing, you hear something a little different and you perceive it more pleasing. Whether or not one is better than the other is up for debate. Especially when you get to a certain point. There are trade-offs for everything when it comes to audio. FUN, FUN, FUN!!!

Japosey,You are absolutely right in what you say.You think you are happy with something and then you hear something else with a different set of strengths and this captures your imagination.
For many of us once we hear really good imaging which is most often a combination of a really good preamp and either point source or electrostatic/planar speakers there is no going back.This is what happened to me.Around the same time I got the chance to have extended listenings to both Goodmans Axiom 80s and E.R. Audio electrostatics.Although completely different speakers-the Axiom 80s a high sensitivity dual cone driver and the ER a low sensitivity full range stat,they both set benchmarks for imaging.
These systems also used Supratek preamps which of course are also known for their amazing imaging potential.
So now most systems sound very two dimensional to me.

JT

i appreciate with cones/single drivers you et a good image, but they are completely useless in the bass, or high frequency extension IMHO

I've made a couple of horn speakers, and whilst they do sound great for a while - great imaging, the rest of it can become very unsatisfying.