Overall, fairly impressed. The material is similar to the Classic Army G36 nylon fibre. It's textured, feels good to the touch, and is quite solid. Other than the foregrip (see below) there was no noticeable body flex anywhere. Even the magwell is very, very solid. It doesn't shine like ABS plastic bodies.
Most of the gun is made out of nylon fibre. Metal parts include:
-The outer barrel (machined aluminium, very nice)
-Cocking lever assembly (the swivel lever itself is still plastic. It feels stronger than the stock one on my CA that broke rather quickly. User beware though).
-All body pins and screws
-Threads for the rail holes in the foregrip
-Rear sling mount, rear stock spacer
Aluminum outer barrel
The fake gas tube assembly and supporting mount (the one that supports the inner barrel) is plastic. As the one on my CA is metal and very solid this is slightly disappointing. It's plastic on my KWA as well and while I haven't had any real issues with the plastic one I expected a bit more from Ares. Having said that the inner barrel is completely solid. No wobble or movement whatsoever.
The only real disappointing part of the build is that the rear of the foregrip is slightly wider than the upper receiver. This leaves some ugly body gaps of about 1.5mm on either side of the receiver and allows the foregrip an ever so slight play to the left and right. The seams in the grip stand out a little bit more than on my G36, but I suspect that's because of the grey instead of black body. They're very subtle and only barely detectable running your finger across them.
SL8 foregrip gap
Non-existent G36 foregrip gap
One thing that REALLY annoyed me is that there is no ball-bearing in the selector switch. This means there is absolutely NO locking of the selector in any position. When I took the selector off the spring to hold the bearing in place is there as are the locking holes, so I suspect the bearing was either mistakenly left out or fell out somewhere along the gun's journey (both selectors were loose when I received the gun). Either way this needs to be rectified before it can be gamed. After talking to AG I learned this gun was their shelf model for about a month and pawed a bit, so I suppose it could have fallen out at some point while being handled. IMO this still doesn't speak well to how secure the selectors are from the factory.
Also, this gun is suppose to have a functioning bolt catch. Mine doesn't work. Looking at the diagram in the manual I can't see quite how it would work anyway. I'll have to wait until I take the gun apart to look into this further. If it does indeed have a functioning bolt catch and I can fix it this will be a pretty awesome feature.
Nifty things I like about the construction
Three things here.
First, the foregrip having holes to mount an underslung rail with metal threads. Not something I'm likely to use, but a bonus nonetheless.
Second, the magwell pin is SPRUNG like a foregrip pin. It doesn't use a retarded nut that strips and gets lost to hold it in. This is an UBER WIN as I've stripped those pins and they have a tendency to work themselves loose (I've lost the nut on one of my G36's).
Third, and I'm kind of neutral on this one. The outer barrel has to be unscrewed to get the foregrip off. This is advantageous because if you either lose the forgrip pin or forget to put it back in the foregrip will be held securely by the outer barrel. The piece the outer barrel holds against is pretty solid and even under moderate abuse I suspect it would hold. The disadvantage is that the outer barrel has to be unscrewed to get the foregrip off and install the battery.
Foregrip threads into a fixture on the other side of that little bulkhead
Other thoughts on the construction
There are a few scuffs that look like they were from packing and shipping. I personally don't care to much about minor marks on my guns but some people do.
Comparing the construction to my Classic Army G36 I'd have to say I'd be hard pressed to pick my favourite. I think I prefer the texture and overall feel of the CA one more, but that's mostly preference and probably no small amount of familiar bias.
Not much to say about the sights. The SL8 comes with the “standard” SL8 long rail with open sights. The sights don't have a small aperture so precision shooting my be tough. I'm planning on scoping it anyway so it doesn't matter to me. The rail is a standard picatinny rail. The rail is either plastic or nylon (I honestly can't tell) and is quite sturdy. You could carry the gun by it if you had to. Like all G36 models, the rail is removable.