Suggestions for arm to replace VPI 12.7

I am thinking about replacing the 12.7 tonearm om my VPI Classic 3 turntable. My budget will be about $4000, and I'm willing to buy used. Does anyone who has replaced a VPI 10" or 12" tonearm have any advice regarding a compatible replacement?
The new 3D tonearm is terrific. I upgraded to the 3D arm on my Super Scoutmaster Reference rim-drive and it is a substantial improvement over the 10.5i arm IMO.
I'd love to know how the 3d is compared to a Graham (I know-read the review but tough to get an honest vpi review with the dollars they spend advertising-even MF didn't knock the MDF $30k DD TT)). Does anyone know if you can easilly replace a 10.0 with a new 3d w/o redoing armboards? I would do that in a heart beat. I have a hopped up VPI tnt jr with 10.0 jmw.
Have you looked at the Transfi Terminator tone arm? Dave Garretson has one on his highly modified VPI TNT. Read some of his threads on the subject both here and on Audio Asylum.