Conrad Johnson--does anyone use this brand anymore?

I think OP was specifically asking about CJ phone preamps. The CJ linestage preamps need no endorsement.

+1 on gears need to match. Some CJ preamp models tend to have unusually high gain and depending on the pairing amp you may not be able to move the volume control past 9 o'clock for most listening conditions. Check the (gain) specs carefully before committing.