They both pratically the same. The infinity just had its recent firmware updates. The crystal has a built in mc manager which controls the chip. Infinity also has dvd dual layer (dvd9) but crystal should get it in the next update. Another difference is that you need a hacked firmware for the crystal chip for backups which a fully made firmware wont be found here. You can get it on google though. You cant go wrong with either one though.
scph-50001/n v9 matrix infinity fw: 1.91
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