I'm with Colin, the saving gained by stretching intervals isn't worth it and if it's your baby it's ok to spoil it. I always change the filter every time I change the oil and I do that at least every year regardless of whether im using mineral or synthetic oil. Overkill yes but then no engine ever suffered from too many oil changes and if your doing short runs the nasty stuff will build up more and condensation won't get burnt off. If you lay your car up over winter then change it before storing not after.
Cambelts do deteriorate over time, change always on the guidelines. My LR should go to 140k but I did at 80k and on age. Looked ok but peace of mind is important and who wants the bother and cost of it failing?
