No experience, but I have used the 8" with the steel frame and phase plug.
I believe the cone is the same throughout the range, so I would expect tonal differences over the cast frame version.
I found the 8" to be quite good, IMHO substantially better than the Fostex FE206E.
It obviously doesn't do bass (not enough Xmax), but the treble is pretty flat to 12kHz (beaming dramatically of course), and isn't all that far down at 15kHz. No nasty sub 20kHz peak.
The midrange unfortunately, again in my opinion, isn't as good as a dedicated midrange, but overall it is a pretty balanced package.
David
