PTS Masada Gearbox Shell

[DarthLakey]

One of the oft cited failings of the PTS Masada is that it's proprietary gearbox shell has a tendency to crack, and replacements are a PITA to get hold of. While the A&K has worse externals, it is TM compatible, except for the nozzle and hop up (CNC'd versions are available from Ehobbyasia). Reviews are mixed on both of them for these reasons. However, while trawling the internets, I found this CNC reinforced gearbox shell for the PTS Masada:

http://www.aztecairsoft.com/#!store/c1yws

So what do you guys think?

NB: Would the GBBR kit from EHobbyAsia get seized at the border? Technically on the Masada it's the upper that make's it a firearm (that's what's serialized). However, the kit includes a lower receiver, and I don't know how well versed the CBSA is in that kind of thing.