I have 180 of them.

 

1) Is it worth killing them without a cannon?

2) Approximately how long would it take to do with a cannon?

3) Approximately how long would it take without one? 95 Att, 94 Str, using pure sets.

1. no

2. can get about 450 kill/h at max abilities, so i'm guessing with your ability about 30-35 mins

3. 2-3 hours probably, lol.