IMHO using (claimed 100% by the vendor) compatible optics...so non genuine HPE Aruba...on machine of that class...is somewhat that can be considered dangerous.
If the FS J9150D-C is claimed to be 100% compatible by its vendor/producer...any possible issue that can be bring back to that part and that impact to your Aruba 8320 could easily invalidate its warranty or make it difficult to support you by Aruba Support TAC compared to what will happen if you used 100% original genuine supported parts.
We have a VSX (two Aruba 8320) and sixty genuine J9150D...it was not cheap...but we are on the safest possible side...for just two cheaper items (how much cheap then?)...if I were you I would not risk anything when working with Aruba 8320.