I have a couple of older Radio shack telescoping masts and find them very convienent. I have not fully extended them in years, so they are very ridgid with the thinner uppermot sections still in part of the lower sections. I have both about 15 feet above the roofline with no guy wires and get practly no sway, and this is windy West Texas. The other great advantage is the ease of getting them up. I find it much easier to push up the sections than to fit aditional masts into another while holding it off the ground.
Yes, I am sure shipping is expensive. I do not know if Radio Shack will ship to the store for free, I heard on this forun at one time that True Value Hardware will provide that service.