Pretty straight forward concept. Which ink: 1) Is the cleanest? 2) Dries quickest? 3) Doesn't congeal quickly? I found Wilson ink is pretty messy and doesn't dry quickly. I found YY ink has some issues with congealing if it's not used a lot.
I've tried the above and a few others which all seem to be pretty similar. I've just started using the Babolat "marker pen" style one for the first time and it does seem to work quite well but not sure how long the nib will last. It's certainly the cleanest so far.
YY and Victor solvent base ink is pretty good to me. Just don't use Babolat water base ink, can't stick to any string. No no for marker pen.
I use Pilot Super Color Marker which is approved by USRSA . The problem is the ink stick to the cork and then transfer to the other rackets, every rackets that hit the shuttle will have some of it at the end of the day.
Tecnifibre from MBS is pretty good, looks exactly like the Yonex stuff. Couldn't see any difference. Would not be surprised if they are the om...