Back In February, I had a pair of JBL 4430 Studio Monitors shipped to me, and a friend helped me, by suggesting a couple, and I went with R+L Carriers.
Total weight was estimated at 350 lbs, they were nylon strapped to a full size skid, and the nice thing about R+L (make sure other shippers have this if you decide with somebody else) was that they supply thier own Pallet Jack, and the 53' Semi Trailer had a hydraulic lift gate on back. Thus, not incurring any extra cost with Fork Lifts, etc, so this is one important consideration.
Another point, is if you can have shipment go to-from a commercial address, usually the charges are less, rather than to a residential address.
R+L appeared to be quite professional, quick, and down here in the Southwest (NM), it appears Holloman AFB, and White Sands Missle Range use them as well.
Hope this helps, Mark