I think the only real difference is that the ignitor 2 won't blow up if you connect it the wrong way around.
Thing is, if you've got stock points that are set up properly, you don't notice a difference moving to electronic ignition*. So in that scenario, it's just an increased service life that you're buying. That's fine, but if I'm doing less than 5k a year I won't bother with it.
Now on the bug, I'm doing about 30,000 miles a year- that's got a Velleman transistor kit. Cheap and cheerful, but maybe you don't want project boxes and stuff littering up your engine bay. Haven't adjusted it in three years, check it every six months or so, dwell is still bang on 50 degrees.
In summation- If you're worried about the cost buy the Ignitor 1 and watch the polarity on it. I'm not against electric, I just don't find points so inconvenient that I'd spend more than about a tenner.
*honestly, you won't. Unless your engine goes above 6k, you won't get points bounce and the electronic ignition will do exactly the same thing as your old points.