This is a horrible antenna, but locals use it with decent results. I'd run away .... FAST!
Mechanically it is a pile of junk. This antenna uses thin wall, corregated tubing. As long as you make a good electrical connection, you will be OK. But, those small gaps WILL let water and air in! These two elements WILL cause corrosion and oxidation. Its a ticking time bomb.
Electrically, it WILL burn out if you use too much power! They use PLASTIC instead of teflon or delrin. I've seen a melted coil section and it wasn't pretty. They also use multiple shortened radials to compensate for full length radials, and as we know, full size elements are ALWAYS better than shortened or loaded elements!
You will spend close to $80.00 for one, and have a $25.00 antenna for your efforts.
On the up side, it is a 5/8 antenna and a 5/8 is a 5/8 is a 5/8. Use it with low power, don't expect it to last long, and be willing to put up with the lossy matching section, and you'll do fine!
If you want the best, get the I-10K! If you can't afford the best, get the Maco V58.