I've shipped quite a few motorcycle engines, and a couple of complete motorcycles, through Forward Air. They've always been completely crated, but I've seen a lot of various items on pallets when I've been there.
Forward Air is usually the cheapest, and they have terminals in most major cities, usually at larger freight airports. They're HQ'd here in Columbus and they're open 24/7, which makes it convenient. They're quick, and I've never had a problem with them damaging or losing a shipment.
From a shipper's standpoint, they're a bit of a pain as you can only pay with a certified check/money order (unless you have a corporate account). Which means you have to go to the terminal, have them take the crate out of your truck and weigh it, then go to the office while they figure out the charges, then drive somewhere and get a money order, drive back, and complete the paperwork. Not the quickest or most effecient process.
From a receiver's standpoint, if there's a Forward Air near you, the only negative I've found is you sometimes stand around a lot until they find the "right guy" to help you out. They're clearly set up for commercial shipments, and having consumers in shipping or receiving sometimes tends to be an exercise in patience.
If you check with other freight companies, look at Terminal-to-Terminal shipping, which works like Forward Air's model. It's often less than half of what they charge for door-to-door service. UPS is now in the Freight business, and I've used them a couple of times with good results. They're usually a bit pricier than Forward Air, but there's a lot more UPS terminals across the country, and they also accept checks, which makes shipping a lot easier.