Well, awesome! I had no clue they had two versions. Why in the world would they make one that did not have the save data option? Thats just insane.
Saving data wasn't all that important when it comes to the original orange-label games (and later turbochips, to a lesser extent). The passwords are short and the RPGs few. When the Boosters were released, it was nice to save hi scores and Neutopia files, but that was about it (DE1 and DD don't access back-up RAM).
On the other hand, the lack of stereo sound kind of sucked. Just listen to China Warrior on headphones - it rocks and the tunes are full of stereo imaging! Memory was expensive and the plain TB was much cheaper at $34.99 compared to $59.99 for the TB+.
Obviously, making two models was stupid, both were overpriced, and I'm just playing devil's advocate here, but I can kind of see why they did it.