Speaking from experience, I went through a Tandem Progression of 4 jumps before I got my own container. I think that doing the initial tandem jumps gets you out into the air without having the stress of dealing with any of the malfunctions that can occur. Personally, I watch people doing S/L and look back at the fact that most of my initial exits were not what is needed for a clean opening on static line. And with a 5 sec delay before your chute's opened for you, your arch needs to be good. Not much room for any margin of error in my opinion. I know for a lot of people it's a monetary issue, but if you can squeeze the extra money to do it the other way, I feel like you learn a lot more from the feedback of the instructors actually being in the air with you.
Blues Skies all!!!!