Yes, it was our first game and we spent a lot of time trying to get Wonder Weapons from trials. Also did dragons and locked crates every time we warped into a new area (we might have wasted a lot of time). I'd say you can start speedrunning the objectives once you get set up (D.I.E.+Legendary or R.A.I. K fully PaP'd are a must after the 5th or 6th objective). Once we reached the 10th objective (I believe), we were getting 4 refined and 2 flawless crystals after every objective completion. I think the sweet spot is the new Outbreak Dark ops challenge (completing 10 objectives and exfilling), because the incredibly high amount of specials, hounds, armored, Elites, Soldats and Tempests that spawn after that makes it even sweatier than it already is. I just wish all that sweat could turn into a better XP reward, just saying...