I have a K-60, and as John said, it is in it's element when you decide to go on the roof. And if you get the 5/8" cable, it is usable in 1 1/2" and 2" lines. The 7/8" open wind sectional cable will fit in 2" pipe, but you can't get too much of a cutter head down a 2" line with the 7/8".
The things I don't like about a K60 are: Setup time. A drum machine, you carry the machine in with your gloves and outlet tester, after your first trip in with a mat and whatever you need in the way of pliers or the like to get access. A sectional such as the K60, you go in with the mat and hand tools, then come back in with the machine and maybe the guide tube, then a basket of cable and gloves, then put the guide tube on the machine, then start running the cable down the line till you hit an obstruction, then once you hit something you feed the last section of cable back into the machine, run the machine to get it through the blockage, then push more cable in to make sure that you got all of the blockage. Then pull the cable back out and feed it back into the basket, trying not to get sewer juice all over the place. A drum machine, everything to do with the cable and the machine comes in at once, no hooking or unhooking sections of cable, the nasty cable gets fed back into an enclosed drum. 2nd thing I don't really like: power. When you get into some really bad stuff, the K60 doesn't have the power to rip it loose. You have to pull it back from the clog, let it speed up, then chew away at the clog bit by bit. Doable, but that takes more time. A bigger drum machine can build a lot more torque.
That said, if I have to leave on a job with only one machine, it is the K 60 with both 7/8" and 5/8" cable. In fact, that is what stays on my truck. I only load my K375 (much like your 380, someone already changed the 375 open drum to a 380 closed plastic drum) when I think I might want to clean a drain from the inside of the home. I need a bigger machine for the really bad clogs, but am not ready to buy one just yet.