I need something to rig up my new tarp, but I don't know anything about the various guyline options. What's the difference between Dyneema, Amsteel, paracord, etc.? What's the best (light, strong, not too expensive...)? And where can I order some quickly? I was going to order the 100' spool of Dyneema from Warbonnet, but I don't think it would arrive in time (have a trip planned for the 28th). Thanks for any info/advice!