I wanted to say I got the Pangea stands in this week and at just under 50 bucks including shipping I am very happy with them. Though I didn't fill them with Sand, you can do so to weigh them down if you are worried about them tipping over. You have to put them together yourself and all tools and supplies are included. they are not perfect as the tubes are not perfectly parallel with each other nor are they symmetrical with each other, but the main thing is that they still look good and are level so that the speakers are level when you place them on top. You also have to attach the spikes yourself as well, so you need to make sure that the screws are fairly even.
Performace: They work great, my Sierras fit on them very well and stick to the Included rubber bumps that you can attach to the stands, i would guess for isolation purposes. I also noticed an immediate improvement in the sound from having been on top of a pair of Polk LS50s for the last 2 months. the bass seemed more detailed and with the tweeters now on ear level the soundstage seemed to open up as well. again this probably would have happened with any set of stands, but now i understand that I really shouldn't have had these on floorstanders to begin with. Anyway. these things are a great Cheap and Cheerful Item especially at 29.99 +shipping for metal stands.