I don't know anything about the Koga. All I know about the Thorn is what I've gleaned from the internet. It seems like a solid tourer. I have an LHT. I bought it after hearing tons of praise from owners via the internet. I like it very much. It's much more than adequate. I also think it's a really good value. If you have only enough for an LHT but no more, buy it. You'll be satisfied. If you have more money, there are other bikes. Whether they're better than the LHT or not, I don't know. I can't see how they'd be much better.