+Crit is far better than +Eff for crafting as it gives you better/more stuff on a crit, eff just means less time taken.
As such I would of put Smugglers a head of Troopers for Armstech more Crits better than faster crafting.
I agree especially with crafting armor & weapons.
You receive exceptional or mastercraft items only on a successful critical roll. Considering how low the base change is, it seems a +5 crit bonus already doubles your chance.
Usually you only care about mastercraft items once you unlocked high end artifact equipment which are very expensive to craft. A +5 crit bonus becomes mandatory to conserve nerves and resources. Otherwise you are just throwing away lots of money, blue and purple mats. It even worse when crafting items with resources only acquired in hard mode flashpoints.
However I'm unsure if a crit bonus also increase your chances when reverse engineering.
For scavenging I find a high efficiency bonus more beneficial than a crit bonus.
If you are crafting a lot because of reverse engineering to unlock schematics you have a high demand inmaterials. High end stuff obviously requires high end mats obtained by high level scavenging mission that takes a really long time to finish. When a mission takes 40 minutes +15 eff beats +5 crit by a mile.
If you are going for pure resource gathering I recommend to prefer high eff. If your focus is on schematics, missions plans, slicing etc. crit bonuses precedence.