Nice rifle :)
Here's my take on the Mk2 I've had now for 5-6 months....speaking strictly on the design above, or the original one.
The Mk1 blows both the Mk2, and Mk4 rails away in terms of engineering, and design. There's so much time, and labor involved in them that they truly feel "one off".
Where the original Mk2 shines is in the category of "bombproof". There is no other rail on the market outside of a one piece chassis like the monolithic railed MRPs that can rival what the Mk2 brings to the table in terms of toughness, durability, and overall robustness imho.
I believe it's even tougher than the Mk1 simply because of the Mk1's much more intricate steel insert acc. rail mounting design. The "shelve"/backplates on the Mk2's acc. rail attachment design is unbeatable for shear strength.
Most new naked rails have simple screw in panels....aka screws into aluminum rail itself including the new badass LMT LM8 slickside chassis, and the new KAC rails. The other common design nowadays we're seeing is the Keymod which works really well for streamlining attachments, however imho it's a less secure method of attachment than the Mk2's design. The Mk2 cuts the cost of the Mk1's steel insert design, and still manages to incorporate a superior mounting design in terms of attachment strength to the standard screw in panel design, the Keymod design, and the Mk1's design.
While I don't think it will lessen the Mk2's overall robustness by much, it's obvious that shedding that much weight in a design will render it more vulnerable to structural damage/breakage. The Mk2 originally is far more robust than any end user I can imagine needs, so the new design has plenty of leeway to give in the robustness category.
obligatory Mk2 pic :)
http://i888.photobucket.com/albums/a...DSC08155-1.jpg