I don't think it's just a terminology change, though. Compels can be refused, Invokes for effect can't.
I'm not exactly sure what you mean by that. You can spend a FP to refuse the compel that is generated by the invoke.
Here's the advice I've given:
Invoke for effect: (similar to what Sammael said)
For effect is good for when you want to do things with cool effects (like having the guy with the super-powerful sword drop his weapon at a very inconvenient time. It only works, though, if the guy accepts the compel. He can pay a FP (if he has one) so as not to drop his weapon.
A trick I've seen is invoking for effect on an enemy that has recovery. If you inflict a mild consequence on them - and they're likely to heal it before an ally can tag it for a bonus, I'd invoke for effect to maybe have them fly back into another zone(like out the giant glass pane window because it happens in the movies all the time). Best case scenario (if the GM is generous) they have to spend a sprint action moving back or worse case they spend a supplemental (if they don't have a speed power) to move back into your zone.
Tagging for a bonus is especially useful for tough(or regenerating), fast opponents. If you find someone overly tough or hard to hit, generally, you want to stack up as many bonuses as you can for one big hit that will really hurt.
Lots of small hits miss or just will whittle an enemy down and take a long time, while one big hit is more likely to take someone out.