I own a BSA B50 with an amal it's not fantastic but it is easy to work with.
I have been at peace with Amal carbs ever since I handled the 1st brand new one I have ever touched a few years back.
I had tried to help a friend get rid of some rough patches and couldn't so i suggested he get a new carb, thinking he would pop down to the local wrecker and buy a Mikuni of about the right size.
But no, he bought a brand new Amal complete with both the same jets, needles and slide as standard. I put it on the bike for him, following the instructions to the letter. It ran well out of the box and even idled (something it had never ever previously done). A minor adjustment to the slide cut-away and it was perfect.
I have stopped bagging Amals since then.
p.S. To be pedantically correct i have "handled" new Amals previously, as fitted to various Bultacos. In my defence, Spanish Amals left the factory on the outer ragged edge of tolerance and were usually rooted after very few hours. Mikuni carbs were and remain the best option to relpace them, but the availability of new amals from England at least gives an alternative.