I found that the drip method was quite easy. No need to buy a tool if you have an extra injector line lying around. You can make one!
I set the timing on my '82 240D using this method and had great results. The reason I set it was because I had replaced the timing chain and just wanted to make sure that everything was as it should be. Get the Haynes manual. It has good instructions on the drip method.
Kevin