It really depends on what area you're talking about. If you are speaking about Luftwaffe ground troops, the splinter pattern tunics were fairly common.

Regular splinter pattern M35, M40, M42, M43 and M44 tunics and splinter pattern pants were all private talor pieces and were therefore not all that commonly seen.

What was commonly seen were splinter pattern parkas and splinter pattern winter pants. These were especially common after 1943. You'll see a lot of Ostfront pictures during the winter after 1943 with Heer troops wearing the splinter pattern winter parka set. Helmet covers and smocks were semi-common, as those were also issue pieces.

Hope that helps.

Langemann