I have the takedown model in 9mm, it's a newer generation one.
I have found it to be utterly reliable. I've had a single failure to feed with it in maybe ~500 rounds (and I shoot cheap reloaded 9mm). The build quality is excellent, and accuracy is quite good (I haven't bothered measuring, but it is extremely consistent, at 50 yards 1 inch groups are very doable). I do have some issues with it that are design related:
1) The mag release is absolutely terribly placed for a right handed user, first time I took it out I immediately dropped my mag by mistake. You have to grab it further down the handguard.
Yes, but only when compared directly to the ergo's of an AR. Other platforms have done just fine without that style release (AK, Galil, VZ58, M14 family, Tavor, SA80, Steyr AUG, FN-FAL, and to some extent the MP5)
2) The spring is very stiff. By far the stiffest of any rifle I have so racking it can be challenging, especially as it gets dirty.
Agreed, but breaks in quickly
3) The requirement of 3 different Allen keys for takedown sucks. The saving grace is that (in my opinion) you very rarely need to do a full takedown, so the only one you need to unscrew is for the bolt handle, the bolt then comes out the rear. Oh, and you need an AR wrench too (the newest ones do away with that requirement, but I don't find it a big deal).
THIS X1000 !...some people just can't it through their heads that while YES it could have been done better...you don't have to do a complete strip after each use. I tear mine down maybe twice a year. A good cleaning can be done just removing the stock/buffer/bolt.
4) No bolt hold open on last round. Oh well.
Yep, it would be nice but it not that big a deal either...again, look at the MP5 9mm, probably the most prolific 9mm sub-gun ever.
So overall it's not perfect, but for the money (can be had for < $1000 new) it has build quality which rivals the XCR, RPR, or other much more expensive rifles. And 9mm is quite affordable compared to other centerfire rounds. I have no plans to sell mine, it's a keeper.