Re: WF or DT for 3wt.
I would go ahead and call G. Loomis and asked them what type of line they designed the rod around. They will be hesitant to recomend a brand of line, but just let them know you want to know whether it was DT or WF.
When I got my Sage SLT 383-4 I talked to a number of the "ultralight" folks who fish 3wt and under for just about everything. The overwhelming used either DT or Wolff Triangle Taper. The consensus was that while WF would work in many applications, the rods really came into their own with a DT and could roll cast farther and more accuratley. I am not a good enough caster to be able to tell the difference, but I did call Sage and they said DT all the way for the SLT...and most of their 3 wt and under (graphite) rods under 8 ft.
Here's my cheat sheet I came up with after reading numerous posts on numerous forums.
Rod is 3wt and under
Rod is under 8ft long
You plan on fishing tight quarters
You plan on roll casting alot
*You have a 4wt that is moderate action or slower no matter the length (just my experience and casting tempo)
Rod is at 4wt and higher (4wt is med-fast or faster)
Rod is over 8ft long
Distance is your goal
You will not be doing alot of long roll casting
Wolff triangle taper if:
You have a 3wt over 8ft long that you plan on using just like a 4 wt of equal or greater length
In your case I would try the wolf triangle taper when it's time to replace your current WF line....YMMV.