I've spent a lot of time adjusting and working on both the stock carb and a Weber. The weber I only read the adjustment procedure a couple of times and now I can easily do it from memory. The stock carb I still get the book out every time I work on one. The Weber is just so simple to tune, you can do it in 5 minutes with one screwdriver.
If you go with the Weber 32/36 progressive you get a dead simple carb with a lot less moving parts than the stocker. The airflow and fuel delivery are much improved, and you can expect not only an increase in HP, but usually also better mileage too. (At least once you get over the initial "playing" around with the added HP

) The only fault really is that the Weber will usually not pass the inspection part of emissions testing. Regardless of whether they put out more or less crud into the air, they have not been certified so they are not allowed.