SA Industrial is PBT, right?
so I think you should use a ruler to check the distance between the two outer mounts of the spacebar.
a while ago, I bought a G20 set from SP:
Show Image
(http://i.imgur.com/4CivcMZ.png)
(G20 top, OEM bottom)
the distance between the two outer mounts is 99mm (G20) and 100mm (OEM)
so if I put the G20 spacebar on my keyboard, it's tight so the spacebar is not as bouncy as expected (the OEM spacebar is fine)
---
I emailed SP and they sent me a replacement which works great.
Wow, great to know. I'll have to measure!