These are 3-way speakers, passive, 4ohms, 1Kw DC / pregnant.
I use an amp with Amcron MT 1201.
The sound is balanced, powerful. It can even add sound in the bass (bass drum) where most full-range speakers do not follow.
Indeed, equipped with 2 15 inch speaker, their frequency response is 35Hz to 20,000 Hz
All this is priced at sufficiently large (L69 * H90 * p43) and a weight accordingly (I do not know, but it's heavy!).

- How long have you use it?
8 years

- What is so special that you like most and least?
The +: sound, best I've used fullrange.
power
the - the weight and bulk. wagon, SUV or van required.

- Have you tried many other models before buying it?
yes, with DAS, Electrovoice, JBL ...

- How would you rate the quality / price?
Zeck is very expensive, but it works to hell ...

- With experience, you do again this choice? ...
Oh yes!