You shouldn't have any problem at all with 'action', what the RC STX's do fault on is not all their jerkbaits lay in the water right. it's probably 65/35% bad to good ratio of how they're suppose to act when it comes to suspending, sinking, fast float, tail up etc. From the majority of bad ones, you can correct them by adding cut up suspend dots after the bill.
Try working out different jerks/twitch styles along with reeling speeds and keep and eye on your line slack.