I don't have first hand experience since I've never had a vehicle capable of sufficient depth of mud, but I am getting there.

All of my previous vehicles had vented rotors but could not go axle deep in mud. My Discovery had solid stock rotors which I am in the process of replacing with slotted ones. I didn't particularly covet the slotting, but I bought an EBC kit because I've raced on EBC products and know they work. Brembo's street products are lame, sometimes no better than OEM. Ferodo (the OEM for Land Rover) is ok but overpriced for what it is. And I won't buy Proline Pilenga, Pronto or whatever. I don't expect mud problems on the EBC but they're not vented or drilled.

 

But the need for slotting and drilling is a true story passed around by people with engineering degrees and racing experience.

Did you know that slotted rotors are designed to no only perform the function of allowing offgassing or water removal if needed? They also rip down the surface of your brake pads faster to remove the vitrified material created as a part of the liquid-glass transition that happens with pads as high temperatures. Great for the track, useless on the street and trail.

Anyone who wants to argue this should do their research and bring facts to the table. Anyone who wants them anyway is obviously free to do so, but understand you are getting them because you either are misinformed or just like the look.

EDIT:

One more thought here....mud in the slots or rotors, whether it happens or not, has to be totally irrelevant to the function of slots and rotors. I wouldn't even consider mud clearing a concern. It's both too porous and too fragile/brittle to even be a measurable factor.

Besides, slots and cross drills don't even come into play until you are braking like this:

 

I have had the DBA rotors for about 2 years now. It was the first maintenance I did to my Discovery shortly after I bought it. I went with factory LR pads as they were a good deal from Rovers North at the time. I really like the feel of the DBA rotors, and it probably helped that I replaced pads and rotors at the same time. Recently last summer I added stainless steel lines and that made my braking much firmer. Now all lines are hard lines. I went with Atlantic British, which claimed their lines are made some where in Australia. I have put 35,000 on the pads and rotors, 10,000 on the stainless lines. My green brick stops better than before all that. I dont wheel in mud so that not an issue for me.

 

SS lines are really, really awesome for brake feel and performance. The only thing to worry about is keeping up with them. They don't age as well as rubber lines, and tend to hide their problems where you can't see them. But it's a totally worthwhile upgrade if you're willing to consider them an inspection/maintenance item.

 

So maybe replace them every 4/5 years since one cant see if there are are problems on the inside. At $130 its not too expensive if you do them yourself. Now after tackling it. Its an easy 3hr job and probably even faster with a helper to pump the brake pedal.

 

I don't know what to tell you about that on a street car. I run them on the track car, so they don't see salt. But your suggestion sounds reasonable.

 

now that you have completed highjacking my post
1.I do not remember asking anyones opinion of what they thought of drill & slotted rotors?
2. I did not ask how they worked on anyones track car, as Im sure it is not at 2.5 ton 4x4 truck.
3. mud is not a concern as my urban assualt vehicle rarey sees off road, so far.
4 what it does see is a 350 mile commute thru some very windy roads at a good speed, which warps solid rotors quite quickly, and as you say this brick does not like to stop.
5. say "Brembo's street products are lame, sometimes no better than OEM" you sir have never drive anything with a Brembo braking system.
6.The advise on stainless line would be great if I hadden been running them on every bike I own for the last 25-years.
7. DM disc brakes of Australia are probably the best I've seen, but dont fit the budget right now.
So if anyone has anymore spots i can look for pricing great i would love to hear about them.
If you would like to have a debate of drilled vs slotted vs vent please that it over to larry and daryl and his other brother daryl post.
For those who accually answered my question thank-you for the leads.

 

We can go on all day regarding the pro's and con's, bottom line good slotted and drilled rotors, not the Asian rip offs will last a very long time, my first set of pads lasted over 80,000 miles and were only replaced cause they got too hard.
If some one asks my advise I recommend them and have never had a single person say they didn't like them. As for the pads, yes, factory OEM pads won't last long, course they don't on any rotor, but good ceramics hold up very well.

 

Akebono Euro Ultra Premium Ceramic Brake Pads are on thier way, with the driving I do I wouldnt use any other.

 

Those are what I use, EUR 676 in the front and EUR 493 in the rear along with synthetic brake fluid to handle the heat.