In most cases, simply replacing the duckbills in the vacuum pump at 3-5 year intervals will keep it functioning properly, and keep you out front of having any problems. Remember that there are (4) duckbills in the vacuum pump, 2 on the input side and 2 on the output side, and they come in packages of two, so you'll need 2 sets of duckbills to do the job.
The full maintenance kit shouldn't be necessary unless you are having a REAL problem with the head. VacuFlush heads, provided you don't clog them up, have been known to last 8-10 years and sometimes longer without having to replace anything at all.
