It's something manufacturers do not have an influence on. 3360 != 3366, at least SROM-wise. I suspect the internal design is the same but the SROMs differ quite a bit. They also probably contain some kind of a CRC check to prevent the SROM interchange. Some SROMs can be used in different sensors. For example, S3888 SROM works when flashed to A3090 and I think A9800 can use A9500 SROM.