I recieved a Tamiya GF 01 for a christmas present this year, and it is built with the stock motor and esc. I purchased these universals to go with the build. Two of the 4 that I purchased failed in the week that I had off for christmas holidays, and the other 2 have failed since. This is all within 1 month. Two of the universals had the pin come out of the end of the driveshaft, and 2 of the universals simply snapped. Keep in mind that this is only with a stock Tamiya setup with a torque tuned 540 motor. Worst part for me was that I ordered another set when the first one broke, not realizing that the rest would eventually fail, so now I am stuck with thee. This is a 100% failure rate with a very mild power setup. I do not recommend these at all.
Nice to have these parts available to replace old worn Tamiya parts. Especially since originals are hard to find. These are well made and do the job perfectly. They also increase stability and handling characteristics.