Dodgealum, both the xx2 mk2 and Delos are relatively coloured in the tone and timbre when compared to a master tape like neutrality of the ART9. The xx2 will also sound veiled compared to the ART9. The Delos is transparent but it is not as fluid. The ART9 reveals more micro details than either, sounds more sparkling and pure than either. I already said that it is one of the most fluid sounding cartridges I have heard. In that regard it is like a Nude SPU which I had for some time. If you compare an xx2 to a Delos, you will find that the Delos has more bass power, goes bit higher in treble but it doesnt sound as integrated as an XX2. These are all weaknesses that is addressed in the Kleos (as per a audiophile friend). The xx2 of course has a more coherent presentation than the Delos which makes it a bit more musical but probably not as much sparkle or dynamic range as the Delos. Going to a higher Dynavector removes the veil that I had mentioned earlier and improves the dynamics over all. These weaknesses are apparent when you live with these cartridges and hence the upgrade path is available. I do not feel an iota of upgraditis when listening to music on an ART9. It just feels like a great balance of all the musical and audiophile attributes we look for.
Tablejockey, the performance/value of ART9 is extremely high. Compared to the OC9 mk2 you will hear a huge leap in dynamics and resolution if your phono and amplifier is up to it. ART7 needs an appropriate SUT, no point even trying it with an active MC phonostage.