>>6205335>Mech Frame 5The main value these have is the unique parts that make up the frame. Looks like you're expected to supplement these with lego, specifically their mixel joint system.
The designers of the MF5 system did makesome weird choices that really reduce modularity. Their male / female piece (2nd from left) uses a female mixel + a clip, instead of a male/female mixel, so you can't chain together long arms. Instead they used double clip piece for elbows (rightmost part). Really reduces the possibilities.