Depends completely on the type of angling you'll be doing fella.
- For out-and-out distance casting you want a pre-stretched line, something like Fox Exocet. However, abrasion resistance is non existent and they tend not to sink too well either.
- If you want a little more abrasion resistance/sinking but maintain casting then the new semi pre-stretched lines are very popular, Gardner GT-HD, Shimano Technium, that kind of thing.
-Then you have the genuine all-rounders, they do everything quite well. As said above Gardner Pro is very good indeed, as is ESP Synchro XT (NOT the loaded version).
- Then you have what I call snag lines, the stuff with great abrasion resistance but you'll not cast a million miles with it. Think Gardner Hydro Tuff.
No line does everything, you should buy it to suit your needs.
I use Rig Marole SLS Specimon Tough. It's indestructible, has the strength of a snag line (they saw through wood with it in their demo at the shows) but it casts and sinks OK. It's not the most supple but I can hit 130 with the 18lb (0.37 mm dia.) with quite soft rods. I'm no big caster either.