Quality Gems vs. GCPs

I remember reading a long time ago that anything with less than 12% quality was only good for the GCP recipe. Is that still the case? Are there exceptions? With the advent of Strongboxes has the Gem Cutter's Prism lost it's value as a currency? What is your rule of thumb with these gems?

I have been going through my stash, getting all the ones with +% quality together and would appreciate any advice you can offer!

I had way more GCPs in Ambush than ever before, mostly due to strongboxes. When they make their way into the core game next month, they'll be less frequent than Ambush. So I think GCPs will be somewhat easier to come by, but not as easy as in ambush. I don't see it affecting their value all that much. I think they traded 2 chaos for 1 gcp.

12% is probably a decent rule of thumb, but it really depends on the gem. If it's a desired gem, adding 8 gcps to get to 20/20 is a lot easier than using 1 and then releveling all the way back to 20. But a gem like Chance to Flee, I would use to get a gcp from the vendor recipe even if it was 19 or 20 quality since nobody uses it.

Some are better than others when it comes to gem quality.

Gems like hatred and spelltotem have useless quality bonuses.
Gems like empower and freezing pulse have amazing quality bonuses.

Look at the quality bonus see what it does then determine. A little thinking goes a long way.
There is no 12% quality is good 11% is bad.

Looks like I have to judge them individually; once again I'm forced to resort to thinking. Thank you for the replies!