There are total of 30 collections as of now on Art Block Playground. The list of each projects can be seen below.

There are total 36 collections on AB Curated by 36 different artist. And out of those 36, only 17 of them has also released at least one collection on AB Playground. 1 artist has 4 Playground collections, 3 artists published THREE different collections and 5 artists published TWO collection on AB Playground. Full list can be seen from table below.

Now, let's see the total sales volume (in USD) for artists with collection on both AB Curated and AB Playground. There are 17 artists and there are 7 artists which has more sales on Curated and 8 artists with better sales performance on Playground.

(p/s: sales volume for Curated Collection by DCA and Jeff Davis were unable to be obtained)

There are 9 artists that have higher average sales price on their Playground collection compared to AB Curated. One notable observation is that Dmitri Cherniak who created the Ringers collection which holds the record for the most expensive token ever sold; has higher average sales price on his AB Playground collection instead. His Playground collection, the Eternal Pump has recently gained popularity and more scarce than his Ringers as there are only 89 for Eternal Pump vs 1745 Ringers.

Graph below also shows the sales volume for each of artists' collection on both AB Curated and Playground.

So, in conclusion, there are no guarantee that collections on AB Curated will be much more valuable compared to collections on AB Playground. It all will depends on various other factors but from what I noticed thus far, it's basic supply and demands.