I just found this post and wanted to add that they are fabulous dogs if you are up for the energetic challenge 
We have 3 Entle’s, 2 females and a male. The females are full sisters that are a year apart and the male is from a different breeder in Slovakia. I LOVE these dogs. These dogs are smart, smart, smart… You should check out NEMDA our breed group and get in touch with a breeder near you to meet. Several of the people in our group use the dogs for herding, agility, flyball, etc. Our dogs mainly hike with us. We can take them on a 10 mile hike and they still have energy to burn. The oldest just had TPLO surgery and even though she is very high energy, was great during rehab. She LOVES her rehab exercises and I think would love agility. Like the others have said they are very loyal and loving to their people, but wary of strangers. Like any dog early socialization is key. Our alpha female has very strict rules for introduction, so we have to be careful with introductions to other people. Our male is the most un-Entle Entle you will ever meet. Super lazy and always sleeping, but ready to go when asked. He is definitely not the norm.
I really don’t think they have a Golden-like personality. No way are they laid back and relaxed like Golden’s. They have a pretty high drive and guarding instinct. They were bred to drive cattle long distances and guard the herd.
Here is NEMDA’s website http://nemda.org/