I had much, much more fun flying my Ishkur than I did my Dominix, even though the BS was far more powerful and required for the level 4 missions I was doing.
In Evita where I was missioning there were about 4 pirates who would mission scan people. They almost got my salvage ship twice, but they could never scan down the AF.
Most mission busters (at least those, who are doing it for their living) don't bother scanning down anything smaller than a battlecruiser. Unless it's a T2 cruiser.
Mia san de Borg. Aichan Widastaund keannt's aich ind' Hoar schmian.
Bust mission runners accomplishes a few things. It lets you pick up sweet loot drops, it nets you some very nice killmails and perhaps most importantly it lets you practice your probing skills. Start out busting mission runners in empire and it's great training for busting plexers in 0.0. And THOSE are some nice kills.
Two days ago friends of mine caught a Golem in a mission and wanted to ransom it for 4bill (upon ship-scanning it). He wouldn't pay, he died, he dropped a Gisti X-Type XL Shield Booster worth a few bill. That's a billion ISK reward per member for 20 minutes invested, though of course jackpots like this aren't VERY frequent.
Mia san de Borg. Aichan Widastaund keannt's aich ind' Hoar schmian.