We attended the same show (I attended LA/Irvine shows for decades) and I also said hello to him but I think it was in 2015-6 (I’ve owned the 864 and 890, 324 and Acute since 2006, sold the Acute and prefer the 864 phono stage to the 324 for a Dynavector 20X2 L). The huge difference in quality in use was installing a Synergistic blue fuse in the 864 and a purple fuse in the 890. I use Stillpoint SS Ultra footers under the 864 and SR MigSx under the 890.
I don’t know if after what I have done to modify and tremendously improve the 864 is as good, less good or better than the 912 which I contemplate(d) purchasing. I guess I need to hear a 912 with a SR fuse to determine that (your 868L is a 912 line stage). Do you live in the LA/Orange/Ventura County area?