We have made use of the PTP450 in the 3Ghz band for a number of light duty micro sites. These links typically modulate up to 120Mbps, but they are limited by a 100Mbps interface and most of all an inadequate processor that cannot process more than a certain PPS rate, which in our case results in a maximum throughout put of roughly 60Mbps before packot loss becomes a noticable issue. I would rightly assume a 450i would double our capacity, by removing these bottlenecks.
So the question is... will we ever see a 450i operating at 3Ghz? So far, I've had to replace these 3Ghz links with 5Ghz AirFiber links as we've outgrown them. With 5Ghz congestion presenting its own issue, this is not a sustainable path.