i used 89L with my rx-1 with a 151 inch track, worked good, but those weight was'nt really good with a bigger track 162 x 16 x 2.5. I got better luck with 8bu-00 with a huge track.
the keep the rpm steady, but not as good as 8bu. I think with the shorter track, they pull harder than 8bu
i know snowfever on here ran his buddy apex with 89L, but not 89A