Has anyone who is using the 35mm F1.4 noticed whether the firmware update for the A7 cameras is needed for the 35f1.4 focusing accuracy. Currently I find it kind of slow and I was wondering if I should revise my firmware. I'm hesitant because I read something (somewhere) that said that after the firmware upgrade the older 35f2.8 would experience problems. Can anyone give me any information on this question? Thanks.