Here we go, not a comprehensive review by any means, just a few thoughts and opinions about these 3 rifles. If I have anything wrong feel free to correct me and I will update my post.
First off, about the rifles...
All three rifles are chambered in .308 Winchester, all three are reasonably close to the same price range... but that is where the similarities end.
XCR-M
The XCR-M is a fairly new design that uses an operating system strongly resembling the basic workings of Kalashnikov rifles, combined with similar ergonomics to the AR platform. This rifle is built for reliability and durability from the ground up. The addition of a left hand charging handle facilitates rapid operation of the firearm while still keeping your strong hand on the fire controls. The XCR has a fully ambidextrous safety and magazine release, but is only available in right side ejection.
The rifle is equipped with an outstanding muzzle brake that, while loud to people beside the brake, is not oppressive to shoot, and is outstanding at reducing recoil and muzzle jump. This is one of the best rifles I have ever used for shot recovery on target while shooting from prone, you squeeze a shot off, but the crosshair returns instantly to your point of aim. Reliability has been excellent with all brands of ammo thanks to the adjustable gas system, which only requires the rim of a case to operate.
Accuracy is superb, 1MOA capable, with average groups being 1.5 - 2 MOA with my 1-6x optic.
Magazines are widely available in both steel and polymer, as it is just a standard AR-10 magazines. Magpul makes a wonderful 20 round magazine that is as robust and reliable as the rifle.
The biggest downfall to the XCR is the weight. This is a wonderful gun to shoot, but it really sucks to haul this heavy tank of a rifle around in the woods in a backpack to get to your favorite shooting location. Still, I am more than willing to bear that burden to enjoy all the benefits of having this rifle with me on the firing line.
Famae SG542
The Famae SG542 is a Chilean licensed copy of the Sig SG540. If you have ever seen, held, or even better fired off a Swiss Arms rifle, you will know enough to know that you want to own this gun. The SG542 has a few more rough edges than a Swiss arms, and the finish is not to the same quality as a Swiss arms, but other than that, this rifle is a masterpiece of no-nonsense Swiss engineering.
It is right hand charging, left hand ejecting, uses rock and lock style magazines, and does not have ambidextrous controls.
The rifle is lightweight, balances surprisingly well in the offhand shooting position, and has mild recoil with the birdcage style flash hider. Accuracy has proven to be good in the short period I have owned this rifle, with average results being in the 1.5 MOA range with a 1-6x optic, but I have yet to try any hand loads from this rifle.
The rifle is lightweight for its class, and the addition of the optional folding stock makes this rifle an instant favorite for backpacking into shooting locations.
The biggest downfall of the SG542 is the magazines. They are specific to the gun (ie expensive), currently spares are not expected in the country for some time, and I have had reliability issues relating to the follower jamming in cold weather causing fail to feeds. Hopefully an aftermarket polymer option hits the market in the near future.
Kel-tec RFB
The Kel-tec RFB is the only bulpup on this list, and the only "easily" available bulpup .308 in Canada, and that right there is a huge selling point.
It is a completely unique design, as expected from a company like Kel-tec, who have a history of innovative designs. Of course, with innovative designs come quality control issues, and Kel-tec has had plenty of those with many of their firearms, but the RFB seems to have relatively few of these, and mine has run 100% reliably since I have gotten it, despite its complicated extractor mechanism and forward ejection system.
The rifle is left hand charging, forward ejecting, and takes metric FAL magazines, which can be found in serviceable condition fairly easily.
The controls are logically laid out and easy to pick up even if you are not familiar with bulpup firearms. This rifle is truly ambidextrous, just like the Belgian P90, a left handed user can pick this rifle up and use it effectively right after a right handed user, making it a great rifle to introduce people to the 7.62 platform with.
Due to its short length, this rifle is by far the best for offhand shooting, making this an excellent choice for hunters and plinkers, but it is weak at longer ranges as it tends to be tricky to install a bipod on, and I have only had modest results accuracy wise from mine, averaging 2 - 2.5MOA with mine. The mushy bulpup trigger no doubt lends to this, but it is something that is acceptable if hunting and plinking are your goals.
The biggest weakness of the RFB is the difficulty of installing a bipod, and thus making long range accuracy difficult.
All three are excellent rifles for very different purposes, but I won't be selling any of mine, let's just put it that way.
