From what I've read, that company does seem to have good after-sales service.
Although personally I find all those threads about about Audio GD somewhat irritating, especially in the DAC forum.
Once I noticed there were so many threads, I counted the first page and in the first 20 threads or so, 12 were about Audio GD products, that's just ridiculous.
Might just be enthusiastic people who want to talk about new products from a company they like, or something darker, who knows.
I think it would be a good idea if all those threads were condensed into one, similar to the STAX thread, or at least one thread for their amps and another one for DACs.
Myself I wouldn't buy anything from them though, mostly for the reason you mentioned.
I don't like having my stuff being upstaged by a different/new/better model even when the product itself was just released.
Not that a company shouldn't innovate, but it seems like they do it at an extremely high rate, which makes me wonder how much effort/time was put into every model, and how much is "withheld" just so another better/different model can be released soon after.
Of course, with all the new releases, your older models become less desirable and drop in resale value as well, which is another factor to keep in mind.
Just my personal view, although I'm positive the mob is already on its way to educate me about why I'm wrong and all the models in Audio GD's product lineup serve a different purpose, etc.
I just feel they release too much, too fast, because of that they've pushed away a certain group as potential customers, who don't like this.