Topps got creative in an expensive way with 1995 Topps DIII. I liked this set, really....I just can't get over some details which prevent it from being higher on this list.
Design: It looks like the ball is coming right at you! No, it really is... 3D photos coming at you! The cards were thick, made of multiple photolaminar layers to create an illusion of depth. On some cards it worked. Check out the Jeff Montgomery card from the set. On others, it didn't...look at the Will Clark card (the glove is the only thing that pops). The backs were a bright orange with some interesting stats and a headshot of the player in the middle.
Details: There were 59 cards for series 1 distributed in 5 card packs for $4.00 per pack. Now you're probably wondering why I said series 1? Well, there was going to be a series 2, but due to lack of sales and interest, it was subsequently cancelled. The checklist, therefore, lacked a certain cache, only including a few stars of the day (no Thomas, no Bagwell, no Puckett, no Maddux) and with the most known young player being the immortal Bob Hamelin (1994 AL ROY). It is essentially an incomplete set The only insert set was D3 Zone, a 6 card set inserted once every 6 packs, that really only had baseballs showcased at different depths with the player floating in it.
Impact: It was innovative, but failed to deliver, limiting its overall impact. It did nothing to decrease the trend of paying nearly $1.00 per card in a pack, even with its abject market failure.
Summary: Essentially, if it was an action photo, it was a well-executed concept. But with such a small set size, every card should have been to take full advantage of the technology. I'm not ashamed to admit I have every card of this set after purchasing a box for cheap in 2001. I'm currently trying to acquire a 2nd set since the box yielded almost two sets for me. It's pretty fun to look at the cards in a binder, but you do get dizzy after awhile.
In short, the premium cost for what was essentially a technology gimmick limited its overall and long-term appeal. The checklist was weak and too small and the insert set was uninteresting and easy to acquire. There was no perceived value except for the possible aesthetic appeal which was limited to about half the checklist. This is the first set that I pursued that is on this list. It could have been executed much better than it was.