I was planning on building with some mushroom blocks but unfortunately, placing them will always make them show as the same block.

I added an attachment with an attempt at placing 4 different-looking mushroom blocks in order to show what happens.

How to reproduce :

Step 1 : Obtain mushroom block with specific data value with "/give"
Step 2 : Place the block

On a side note, the mushroom blocks (ID 99 and ID 100) will merge in your inventory in 1 stack, even if they have different data values. I managed to separate them by placing them 1 by 1 in a chest and grabbing them after getting all of them.