ZONA tools: worth the price?

Just wondering what your thoughts are on Zona tools. I bought their hobby knife for $8, thinking it was the only one with a soft grip and blade release knob on the back of the knife. A week later, I found the exact same knife, except it said "EXCEL" on the side, instead of "ZONA". It was $4.

So I'm wondering if anybody else buys this stuff, and if you find that the quality is worth the extra cost.

Thanks.