Interesting website.
He looks like his training method is more of the leash-correction model, but I would not say this is a problem if he works carefully with his clients to ensure that they understand what they're doing with this method - I don't know of any dogs hurt by trainers using this method, but I know a great many whose owners caused harm by doing it incorrectly. If you prefer this method to more positive-reinforcement training, he's probably worth investigating.
If you do meet with him and decide to train with thim, I'd really suggest going with your gut. Generally, I think obedience training ought to be fun for you and for your dog. If Loki seems happy, and you're both learning and progressing (assuming you're practicing at home!), then it's a good place. If Loki seems frightened or subdued, then a positive-reinforcement method may be a better fit for him.
I'm confess that I'm a bit off-put by the big advertisement for electronic training collars. I think these can be useful in very specific situations and in conjunction with VERY experienced trainers, but I'd be apprehensive of a trainer who uses them regularly enough to "endorse" a specific model.
Hope this helps!