Large BGAs on both sides of the board

[buenos]

Does anyone have experience in MASS PRODUCTION with large BGAs soldered on both sides of the board?
We made some test boards and they worked, but not sure to design a product like that. I suspect the real issue if there is an issue would show up once we make at least 100-1000 boards, but then it would be too late to redesign it if the yield is bad and we miss time to market.
Anyone can share production yield data on board manufacturing with large (40mm+) BGAs on both sides? Is it doable in large scale?

 

[pjmelect]

I imagine rework would be a problem, If it does not work throw it away.

 

[FvM]

I remember a big problem with old FPGA in ceramic packages that show large differences in thermal expansion coefficient compared to PCB board. These devices used to jump off the board when it was re-heated. Recent flip-chip BGAs have a carrier PCB with compatible expansion coefficient and can be processed in double side reflow solder.

Also rework shouldn't be basically possible.

 

[marce]

The only boards I have done that were covered in BGA's both sides were low volume... So no large volume experience, but we didn't have any issues.