Can't speak to the flash since I don't have one. Have the Marauder .25 and the Gauntlet .22. Marauder better finished, much better trigger, good support from Crosman, outstanding accuracy. Gauntlet trigger can be adjusted very well, but won't match the Marauder, not as well finished, higher shot count than Marauder per fill, Support from Umarex will never match Crosman's, lower price to purchase than the Marauder.
However, for a first PCP, the Gauntlet is a good buy. I think you would like any one of the three guns. If you ever decide to purchase after market parts, the Marauder probably has more available than the other two guns combined. Read all the reviews you can find on all three guns and then decide. If you can find someone near you with any of the guns, try to shoot his gun.