I've been working on an illustrated story off and on for a while, and I can say.....each frame is hours! And the only person I have to make happy is myself.

120+ frames is a ton of work. I know...once you get the scenes set up, you can breeze through several frames quickly, but to get decent looking scenes can take days even after the characters are done.

If this is something you are interested in doing professionally, you should probably sit down and do one for yourself. Do a 2 page thing with 3 characters and 2 scenes and see how long that takes you. Then, you will have an idea what sort of baseline time you are looking at.

Good luck! I think these applications can do this very well, but it's still a ton of work!