Got this guitar about a couple of months ago, so I've had it for a while now and ready to write it up. Firstly it is still surprising that Harley Benton manages to put so much in a guitar that costs so little - fanfret multiscale, thin neck profile, proper bridge, comfortable weight, beautiful finish. Usually a regular 8 string would cost you at least 400 euros, while this, at half the price has twice the features that one would wish for.
Now, straight out of the box it does have one rather big issue - the nut. As many others have already mentioned, it definitely needs work - the strings are too high, don't follow the radius of the neck, and by far the worst part - string slots themselves - the break of the strings (especially D, G and B strings) is bad, i wouldn't expect backfiling on anything under a thousand euros/handmade to some extent, but even so, it's pretty bad, the G string slot had a jagged curve bad enough to snag the string after any bend, would not return to tune, was almost impossible to tune in general. Since I work as a guitar tech it wasn't that much of an issue for me, but for anyone else who doesn't at least have the tools for it, you really would need to visit a tech, otherwise there won't be much of tuning stability. NOW, other than the nut, it is shockingly well made. All the notes ring out great, some 8 strings (MUCH pricier ones have trouble at the first frets of the F# and B strings, this has no problems whatsoever. The neck is rather thin, very comfortable, I was pleased with the playability of it. Frets are leveled rather well too, not perfectly mind you, but again, I would not expect that level of craft at this price nor even if you doubled it (or tripled it to be honest). The tuners could be better, but they do their job. Of all things to change, tuners would be first on my list. The pickups are fine (remember - this is under 200 euros, two pickups alone usually cost about as much as this entire guitar, often more) clean sounds are great, heavy sounds are okay, just a tad muddy, but entirely workable, I wish it had coil split/tap, would've made it a thousand times better, but alas. The electronics are fine too, the volume/tone pots are a bit stiff, but spray a bit of PRF 7-78 (or something similar) and it gets better, or just use them, over time they will loosen up. Overall I had no issues with the electronics/wiring, I suppose it's a luck of the draw thing. The bridge, again, is surprisingly nice, individual saddles look and feel fantastic, are easy to adjust(You will need to adjust them). With 9s on the top it's fine, but once you change the strings (and you really should shortly after getting it, preferably at least a .74 on the bottom, as the strings it's shipped with are far too thin on the B and F#), you will notice that the action is not where it should be, same goes with intonation (these things may vary ofcourse). With that said, almost all guitars that aren't handmade/"premium" have to be set up, so i'm not complaining, rather stating the facts.
After the setup, it's absolutely great!
Also, you have to keep in mind that whatever you're using for a 6 string guitar amplifier wise, especially for heavier sounds, you will need to readjust the settings. Not all amps can carry such a low register in a tight, commanding manner, especially at higher volumes. Not all speakers have the right frequency response for this type of guitar, as well as most amps don't have the kind of EQ section that you'd ideally want with an 8 string, so pairing this with an EQ pedal (or a FX processor that has one) is ideal, then you can really shape the tone to what you have become used to in regards to 8 string guitar sounds. With that said, do not despair and scower the forums for the perfect amp - try out everything that you have, it is surprising what works, I have a 80's Award Session solid state Sessionette 75 that sounds absolutely superb with this guitar (again, not with regular settings that I use with a 6 string, you do need to readjust). Also - try not using too much gain for riffing, the low strings already have a lot of mass and don't really need a lot of gain, the amount of gain on records is often misleading, rather try and pick harder with less gain - it'll sound much clearer and tighter.
In conclusion - great stuff, absolute no-brainer for stepping into 8 string territory.