I bought a pack of three Trend bits.
I've done a male cut, and female cut three dog bone bolt holes and a straight cut in 40mm good quality worktop.
Looking at the bit, it's well used at least half way up, and I wouldn't want to use it again. Is this the norm? I'm not complaining, just curious.
I used to find that unless I was prepared to buy premium quality bits (i.e. Titman or Trend Professional) that the bits wouldn't last all that long and the poorer ones, such as those horrible
Screwfix ones, would actually "scream" when they were going off (i.e. blunt) and even spraying with dry lube (PTFE) didn't help that much - poor bits are poor bits. The Titman/Trend Pro stuff would give me 3 joints reliably and no more, again with dry lube, whilst the Trend CraftPro, T-Tech, etc were nowhere near as good. The problem is that you never know when youy are going to get that one top with a brittle laminate which requires the ultimate sharp cutter.
In the end I bit the bullet and bought a
Wealden Easi-Tip cutter on the grounds that at £3.60 per double sided cutter (bought in tens) I'd always have a sharp cutter to hand and that at two joints per cutter side (you can get three but that's risking chipping IMHO) so I was paying 90p a joint for my cutters. The disposable carbide tips also seem genuinely sharper than brazed carbide tips and produce a better edge (less chips and less liklihood of them). The downside is the £44.00 for the router cutter to start with, but for anyone who fits multiple kitchens that shouldn't be an issue.
I always used to keep an older cutter for the dog bones to reduce the wear on my "best" cutters. This is partly because almost all chipboard can have hard inclusions such as calcites, stone and even the odd screw or piece of metal incorporated in them. There is a percentage of recycled material in most chipboard made nowadays.
I feel that another major factor which influences cutter life is cutter run-out. A well designed collet in good order (clean, lubricated and not worn or abused - with the cone in the router in the same state) will cut more cleanly and show less signs of wear than a rusty, dirty collet in a resin-coated cone. So are you maintaining your cutters, collets and router cones? I do. But then I tend to baby the current "big Bertha" in my router kit - a Festool OF2200e which will have to last me until retirement (partly because I'll be paying for it until I'm 70!)
