I've been using Opti 2 for years now with good effect. I bought a big box of those little packets and although they are more expensive than bulk, they are worth it to me.
Just nip off a corner and squeeze. No more cleaning the dead flies and the dust out of the measuring cup. Did I get it all? No more waiting for the stuff to all flow out of the cup either.
It's pretty cool. You always have to pay more for easy -