Welcome to KVR Dave, your Sonalksis EQ is still one of the very best out there imho.
Kudos to complementing Elisounds AirEQ, which is fantastic, especially at the top end.
I think the AirEQ pretty much proves how extremely well crafted algorithms negate the need for cpu munching oversampling, so I don't see why sonalksis has to go in that direction either, maybe offer it as an option with ultra high quality resampling (but again lots of cpu being used) but better to work on newer algorithms. After all one of the great things about the Sonalksis EQ (as with AirEQ) is the fact that the cpu's so low you can put in on every single track!
I'm really surprised someone here thinks the URS plugs are hi-end, their top end is pretty piss poor and they cause all kinds of other problems too, I think someone was sucked in by the GUI's on that one
Whilst the 517 and AirEQ are similarly priced, they both offer something quite different. Both high quality but very different sounds. I was tweaking a track using one, then I used the other. Then I A/B'ed them to each other. Both sounded different, but I liked both of them in different ways.
Combined they make the ultimate partnership of eq for producing with.
Regarding the TBK, Sorry Dave, i Do feel thats Sonalksis one and only mistake as a plug-in so far.
My biggest problem with it is the response of the reasonance, what happens is as you increase the cutoff, its cutoff peak sounds all nice and bright and buildup up nicely.
But then just before it reaches maximum it suddenly goes very flat, not audible pleasing and not really the effect we're after (and a problem I've never had with any other filter plugin in that way). Which of course defeats the whole point of an adaptive reasonance point. We would like proper control over the reasonance please!.
..oh and ditch those Absolute 2's, horrible monitors. Genelecs will be a big improvement, my personal recommendation though is Dynaudio
Arksun
And I've completely abandoned the Cubase track-EQ, which used to be used constantly; thank god you guys code awesome EQ's that don't use much resources! I look forward to future products from you guys, and beware, I have a credit card now. 
What relates my measurements is how the shapes looks like, so I suppose that if a bell looks like an Orfanidis one, and that I can match the measured bell with an Orfanidis bell, it is Orfanidis.. But it may also not be the case ! 