These antennas are solidly up, I hope they will last a few years. I have an Alpha-Delta DX-LB that I replaced the center insulator with a W2AU balun, and used some homebrew PVC spreaders to parallel a 30M dipole. It is up about 35+ feet in the center, and maybe 25 on both ends. Since I had everything I needed to do it, I also hung a G5RV Junior as a sloper. Other antenna is my die hard 6BTV vertical. The low wires are on Rohn 50 foot masts, one bracketed and guyed (35') and the other with plenty of guys. I am very happy to report everything seems to work fine, I worked a Marconi Special Event station on Cape Cod with 25 watts on the 30M dipole, and a few days ago I worked the Queen Mary station on 40M with the vertical. It's a little pistol station, but it should do all I want to do for a long time to come.
Whew, I haven't worked that much in a long time. I promised Emo next nice day, we will go to the Bark Park.