If you look hard enough on the internet, you'll find people "lining up" to tell you how crappy almost anything is... And most of those people are just repeating what they read from someone else.... on the internet.
I have had a Fobus 2-rail since December. I agree with 444 that they don't move AT ALL, even under torque from the VFG, and that's pretty impressive. Unlike standard handguards, they have notches that fit into the grooves of the barrel nut (or whatever that starshaped round piece is at the end of the barrel/upper receiver) so they are quite solid. I frequently hold my rifle by the VFG, and it doesn't even flex.
Would I rather have a RASII, well... Kinda. I'd prefer to freefloat the barrel, and of course they look much cooler, but I only wanted the rails for a foregrip and flashlight... And I've used the bolt-on rails before, and I didn't like them. They are tough as nails aluminum, but they attach to your existing handguards, which is the weakpoint.
The M44 4 sided rails didn't exist when I got these.... I don't really need the side rails either, but hey, what if I change my mind?
They also fix my biggest complaint about the 2-sided fobus... you have to remove the top HG to get the cover off if you ever do want to use it. Plus, the covers slide a bit when I grab the forend to pick up the rifle. The newer one looks more solid.
The only other annoying thing (as 444 mentioned) is the VFG sliding a bit. But in my case, it's because I'm not using the Fobus VFG, I'm using a more Knight's looking one, and since the rails on the Fobus are "flat in the middle", in other words, the rail grooves are only on the sides of the rails, anything that uses a post that screws through the handle to intersect one of the notches won't work...
Eventually, I want a FIRSCH.