Blue Sponge or Cream Sponge or Orange or Pink or Yellow ... it all depends on how good the quality from the manufacturer.
Normally a Blue Sponge is harder more dense with lots of porous mid-size bubble structures. It tends to be difficult to compress and able to take a lot of speed glue or booster solution.
Orange sponge is just a dense cake sponge almost miniscule bubble sizes, tends to be on the medium-hard and reacts usually to booster or speed glue.
Yellow sponge is another cake sponge with almost soapblock looking tiny bubble sizes very brittle, tends to be hardest flakiest most difficult to cut and reacts extremely to speed glue/booster and very fast maybe even uncontrollable.
Black sponge is a porous springy sponge with large bubble sizes, tends to be made by using "carbon???" to form the porous structures hence very springy but not very good with speed glue / booster.
But this doesn't mean a thing if manufacturer QA and QC are not there .... and the colours are usually just dyes added during manufacturing ... so means nothing ...
I try to be helpful where I can 
Glad some of my EJ'ing valuable to someone somewhere 
) , Yasaka blue sponge , Donic blue sponge , etc etc etc