Coming to us now by way of poster General Noodles on /toy/ is a scan from another Japanese hobby magazine, giving us our first look at the resin prototype of Masterpiece MP-12 Lambor aka Masterpiece Sideswipe. This prototype image shows an intricately detailed version of Sideswipe which slavishly recreates his Generation 1 toy's look with more substantial detailing, and fuller arms. Also of potential interest is a view on the back of the robot mode, which hints that the mold is also being designed in the same style as Universe Classics Sideswipe who fulfilled double duty as Sunstreaker as well.
In the bottom left corner of the scan there's another silhouette of Masterpiece MP-13, the alleged Soundwave, and he's certainly got the bulky look of Soundwave going on there.
Click on the thumbnail at left for a higher-res version of this scan.