I've been using my Traveller now about a year and it's done what I needed it to do. When I've needed a few extra channels, I've made do by bringing along a submixer. Here are some of my thoughts that I hope won't dissuade you:
It's lightweight construction makes it a lousy heatsink if your laptop dumps alot of heat and you set your laptop on the Traveller. I've a G4 PB that gets pretty hot for which I admit to using very little of the power saving features available.
The front panel mixer interface is a bit goofy but works. Dont expect to be able to actively ride a bunch of faders efficiently real time. Cuemix works great.
I'm not sure how much current the Traveller *really* draws but powering it off the FW from the G4 PB really gets the lappie awfully hot. Could be a problem with the laptop coming up short though. Powering the Traveller off the DC connector and everything cools off nicely. It just seems goofy having all of this portable gear but needing extra adapters/cables for power.
Stoking up the Traveller with a full complement of i/o cables gets to be quite a rats nest
This was annoying when the traveller got pulled off it's little table before I got around to duct taping everything. It was enough to scratch through the paint but it still works fine. Next major event out, I'm going to look into a 3-6u'ish rack to help keep the cables, night light, external hd, extra battery, etc. clutter a bit more manageable. Should help speed up setup and tear down time, plus provide a nice flat working surface for the laptop. I swear the volume for all of the cable mess exceeded the volume for the traveller, hd & laptop. The rack will have solar cells to trickle charge while sitting out in the hot sun...
When I bought the Traveller, I got Digital Performer to go along with it. At the same time, I picked up an M-Box with PT LE. It's been about a year now and in hindsight, getting the digi stuff has been pretty much a waste of money. Probably need to move it out... I also use alot of rackmounted Echo Layla equipment, a JB3, and even used a Creatives Nano Zen Plus on occassion for recording <lol> simply as reference.
Simply my mileage...