Hi

STI, known for their 1911 pistols, produced a AR-15: http://www.stiguns.com/the-sti-sporting-rifle/

Mid-length gas system
M4 feed ramp
Wilson match grade barrel
JP single-stage Trigger
Nordic compensator

I own one of em a while, because at that time we didn't have lot of US AR-15 in Switzerland.
(added a quad-rail handguard, magpul UBR stock and miad grip.)
I've fired far over 1000 rounds (only brass) from pmags through it, without any issues.
But only at the range. No extensive use. Cleaning more or less after 3-400 rounds.

I would like to know if somebody here has some experience with one? I guess they are not sold that much, and it seems they even stop the production.
Don't know if it's better trying to sell, which wouldn't be easy.

I doubt you'll get much for it so why not keep it? It's a fine carbine and it's a buyers' market nowadays.

What are they worth in Switzerland?

Till now I'm not disappointed with it. It's very accurate. I just don't know how reliable it would be under heavy usage.
That's why I hoped too find somebody who maybe has more experience with it. Anyway, I not forced to sell it. Just if I don't lose to much.

Why did you say that it's a fine rifle? Do you have information about it?

In general, all US made rifles are much more expensive in Switzerland then the original dollar price.
I've payed 1900.- swiss francs for the rifle, and 1000.- for the stock, handguard, gripp, p-mag and flipup sights. So over all 2900.- swiss-francs.
At that time the dollar has a higher value then today. Then it was around 2400 $.
Now because it's used I would sell it for 2200.- swiss francs, which is today 2600 $

Only from your specs which is good.

The STI is geared towards the competition/3 gun market.

Try asking around at brianenos.com, they may have more info.

Looking at the specs you gave, it seems like a decent rifle.