http://www.tfw2005.com/gallery/showgallery.php/cat/972I got mine last night. Overall, a solid piece, but not without flaws of course.
The build quality is very good in terms of parts fitment & sturdiness, which is a surprise for non-licensed stuff. No floppy joints, plastic are thick enough, and accessories fit tight and sturdy on pegs. The trailer shell may get tricky opening/closing at first. But once you got it, it gets easier after a few tries, especially after the tabs break in. It even got exact matching wheels with rubber of MP Prime. Very nice.
In terms of finish, the grey plastic that forms the shell of the trailer is excellent. Very smooth and shiny just like a Hasbro or Takara piece. Though on the blue and black plastic pieces, they don't have the same finish. Much rougher with blemishes here and there that reminds you this is a 'Knock-Off' still. Some of my blue parts has a couple stress marks too, but that is just mine. Though the blue plastic color does match MP Prime's blue very good. Almost spot on, minus the metallic flakes on MP Prime's blue. Gimmicks work very well. Missiles shoots well and the spring for ejecting the Roller is pretty powerful. Its loud .

The stickers has a glossy sheen on top, not bad. Though the blue stripes for the side often has small specs in the blue that is not meant to be printed there. So its not going to be all clean and perfect. But stickers seem to stick very well. For those that don't care for the retro look, not having any inner stickers actualy don't look as plain as you would expect in person, due to its scale. Looks nice still.
Being a 'Knock-Off' non-licensed product, its quality is pretty high. Though you can still see a big difference versus licensed product. It has its good (functionality, fitment and size) and its bad (plastic finish, flaws on print, less contemporary look, way over priced). So its overall a satisfied purchase and makes Prime a whole lot bigger and cooler, with the fuctionality of the G1 trailer that a lot people missed on the MP-04 trailer. But it definitely doesn't justify the price if you just look at the quality alone, especially if you are a budget oriented collector. Though for me, I am just glad to have a trailer for Prime at last.
I'll give it a 7/10. A solid alternative if you like the trailer G1 style better, or missed the boat on getting MP-04 cheap when it first released.