You have some cash, and you are relatively proficient at slacklining. You want to throw up some longer lines, want to be able to do it quickly, and you want to avoid excessive wear on your stuff. Well, I really only have one recommendation, and it is as follows.

Here is, in my opinion, the best tightening system you can get for your money. It is relatively light, stronger than any webbing or biner you are likely to purchase, durable, and painfully easy to use. I woud say it almost feels GOOD to tighten a line with it: it is just that smooth. Now, to clarify, when you buy the tightening system you get the pullies, no biners, static line, or prussik cord. That is all stuff you have to get separately. I recommend getting 11mm climb-rated static line from your local outfitter. The 11mm will lock the best in the brake mechanism, but is a little more work to thread through than 10mm would be.

This system can provide a 4:1 or 5:1 mechanical advantage all on its own. If you put the brake-pulley in the sling-side, it is a 4:1 rig, and with the brake-pulley on the line it is a 5:1 setup. Using some Prussik cord, ascender, or a Tibloc you can very easily increase this into an 8:1 or 12:1 MA rig. Bomber! The pictures on this page show it in its 4:1 configuration with the Prussik added in for the 12:1 advantage. The only reason I have ever heard of for using the 4:1 system by itself is to reduce the mass in the line to make walking it more comfortable. The difference on longer lines is miniscle to me. A trick line where feel is crucial should be soft-pointed anyway, so it seems to be a moot point.

At any rate, this setup is well worth the money if you are getting serious about the sport. Setting up lines is lightning fast, and if you commonly do it in the same place and have the gear already set up for the paricular location, it is even faster. A nice 85' line I like took only 7 minutes to get rigged the first time, and maybe 3 minutes after that. The best part was that I only had to put it about 4' above the ground. This system got it cable tight without any problems. That was the first time I used the pullies as well, so I had to run all the rope through to start (though I did have past experience with the system). Below are some more pics of the gear. Enjoy!