Compressor encoding vs. Sonic hardware encoding

i searched this topic and found people discussing it about a year and a half ago with Compressor 2, but an answer wasnt really reached.

we are about to send our 60min HDCAM (1080i60) movie off to author and i'm wondering if i should encode it with my new Compressor 3.0.1, or send an HDCAM master to be encoded by a Sonic HD encoder (the DVD is SD 16:9).

my DVD author last year told me that the Sonic encoder is better than software at low bitrates, so we encoded the DVD Extras from BetaSP masters. but i'm wondering if the movie at around 5-6Mbps would be high enough of a bitrate that the Sonic transfer vs. Compressor encode wouldnt be noticable.

we're talking about a $1000-2000 and 2 days of shipping time saved with Compressor, so i'm wondering what people's opinions are. thanks much!

e

4 Dual 2.7 G5s, OSx 10.4.10, Final Cut 5.1.4, Kona LH, Xsan storage
Xsan: Xserve 2.0 G5, 3GB RAM, 2 7TB Xserve RAIDs, Sanbox 5200
Quantum SDLT600A
Sony HDW-M2000/10 HDCAM deck
MacBook Pro: OSx 10.4.10, Final Cut 6.0.1