The sinking line does a few presentations very well. And a tight line streamer rig can do many things well. While the sinking line approach gains me more distance and longer retrieves, the tight line system is great for a targeted approach, with more casting and shorter retrieves.
Tight line systems provide direct contact and direct control, where sinking line systems put a weighted fly line in between me and the streamer. Two different styles.
There are many things to consider, but start with this: What is the water type? And what are your goals?