I have many straps for my Rolex from Horus. Never bought from Everest.
Discovered Krono Straps on instagram recently and bought a pair of Rolex Straps for my Submariner on their website http://www.kronostraps.com
I would say quality is slightly better than Horus. Fitting is more precised and quality of the rubber seems better. Not black and white though, still very similar.
HOWEVER, the PRICE is not the same! I paid 49$ for my straps from Krono. Horus are 125$. What a joke.
I bought a second pair of Krono Straps in their digital camouflage color.
Hope that helps.