The Stihl Rapid/Picco Duro 3 is great stuff.
It has a huge/long carbide plate and features a cutter shape similar to a regular chain.
It cuts very well and does so for a longtime.
My Picco Duro 3 is still great, never sharpened.
Unfortunately I wore my Rapid Duro 3 dull, tried sharpening it freehand but failed - so I stored it in its box till I figure out a way to sharpen it myself/easily.
I estimate to have bucked anywhere between 20 to 30 cubic meters of firewood logs with the RD3 before I decided it got too dull to use.
I bucked about another 6 cubic meters of logs after my first sharpening attempt which was OK. Three subsequent sharpening attempts failed making the loop even less sharp so I suspended further attempts.
These chains do not tolerate impact with foreign objects, the carbide plates will shatter rendering the affected tooth completely useless.
Occasional sand and mud are not a challenge for these chains though.
Once I figure out a way to sharpen carbide tipped loops myself I will get one loop in every DL count I use on my saws.
Stihl Picco Duro 3 (.050" , 3/8" LowProfile/Picco , 52DL)
Stihl Rapid Duro 3 (.058" , 3/8" , 72DL)