Well 2.12 has Trifield width that works. Its broken on 2.5b9. There is bass management that isn't set to correct levels if using the MM port with all small speakers and sub using 2.12. If not using the MM port then not an issue.

Also new Dolby decoding...prologic X in 2.5b9.

2.5b9 sounds a little better but that is just MHO. Really your call.

I remember having to load each file one at a time to get 2.5b9 to load correctly on my 568.2mm.

HT: 568.2mm (Revelation One filter), 518x2, SB3, Bryston 7BSTx3, 8BST, Aerial 10T, CC3, SW12(Qty2) w/SVS AS-EQ1, MK Tripole x4. JVC RS1u, DVDO Duo, Oppo 103 w/Vanity103HD, Sony PS3, VIP 3D Theatre, Acer H5360. Logitech Ultimate Remote and Hub.