Any carb cleaner that you add to the fuel is worth the $8 for a bottle, it wont hurt anything, will clean your entire fuel system, and there is a good chance it will clean out the cause of a misfire.
When you had the carbs cleaned, what was the reason? Had the bike sat for a while and the fuel in the tank went bad? If so did you drain the tank, change the fuel filter, flush out the fuel pump? If not, the old gummy fuel will be sucked into your nicely cleaned carbs.
the ignition is definitely suspect - there is an in-line spark measuring/detecting adapter you can put in series with the plug that will tell you if you have a weak spark. It could be the plug, the wire, or the coil. For a quick check look where the primary side of the coil is connected (to the frame maybe).. if the connection is corroded it will make the spark intermittent.