I have two sn30s and never had any software/firmware issues but the build quality seems wildly inconsistent.
I'm not a big gamer in fact I've never worn a controller out before even as a teen playing hundreds of hours of ff7, thps3 etc on psx with a dual shock controller and the first sn30s I have had at least 100 hours on it and it's in great condition... The second one has less than 100 hours and the right joystick rubber rim has already torn off and one of the buttons is stiff and does not press/depress freely depending which angle or pressure you press it with.
The sn30+appears to be identical to sn30 with a dual shock bezel so I would be very wary.
Any future product I buy from them will come with a warranty either from 8bd if offered or a 3rd party, again, if possible.
This might be a controller mechanics issue masquerading as a firmware issue now that I think about it