Re: Which marker pens?
I use Sharpie markers.
Mainly because they are inexpensive and come in wide range of colors.
When I misplace one (always misplace the one that I 'really need' for a particular fly), I can run down to the local office supply and buy a WHOLE NEW SET (the 'one' I need doesn't come in a single) for only about $20.
Sometimes I'll plan ahead and buy a 'new set' of 196 different colors when I see it on sale for only $99.95. Of course, when I look for it, I can't find where I put it (I always put stuff like that someplac safe, where I won't lose it-can never remember where that is, though) so I'm back to the office supply to buy another WHOLE NEW SET.
All kidding aside, all the permanent markers work just fine. I've used all of them, and can't really see a difference as far as the fish are concerned. Pantone used to have all the best colors, but Sharpie has seen the light and you can get good ones from them now....lots of point options too.
Use what you have, or what you can find. Fish won't care much.
Good Luck!
Buddy
It Just Doesn't Matter....