The tools are fairly inexpensive and its relatively easy to do. I've installed them in hundreds of engines of all types, but there is a pretty frequent need to adjust, polish and tweak a set once you install them from time to time, and unless you have a good feel for how they are supposed to fit both in the block and test fitting the cam into them, you may overlook something that could become a problem once the engine is together and running. Like Beater said, just let the machine shop assume that liability if you don't have the tools yourself or if you've never done it before.
