Choosing strimmer line

[d000hg]

I recently got a Dewalt XR battery strimmer (equivalent to a low power petrol model), which is recommended for 2mm line. Of course they recommend their own line but is there any real difference?
I'm not thinking I want to buy super cheap stuff but rather, is there anything better performing than theirs? I see all kinds of serrated and twisted lines.
Main use is going to be nettles and the like - it works great on these with the small line provided but that's running out.

Anyone have any guesses what rate line is used up? I see it sold in 15, 60, 100+m rolls and no idea what I need. I have visions of buying 100m and still using it in 30 years!!

 

[lostinthelight]

From what I can see Dewalt stuff is not expensive so if its been performing ok why change?
I wouldnt have thought too many folk have used Dewalt cord to make a direct comparison?

 

[SFK]

For reference for garden and some hard use I use about 15m (of 1.6mm) every few years.
i buy the mid priced stuff from ebay that works okay.
never tried the tristed etc, but there are some youtube videos (the one i saw did not show any spectacular results to show any better than another).