Sample Logic did release this week Loop Session Series – Rhythmology (Affiliate Link). Loop Session Series – Rhythmology content and included loops are based on the existing RHYTHMOLOGY. Sample Logic does offer customers who have RHYTHMOLOGY an upgrade path, there is special pricing available until July,  5th 2017.

As Loop Session Series – Rhythmology (Affiliate Link) can be used without RHYTHMOLOGY(Affiliate Link) you may wonder about the difference feature Loop Session Series – Rhythmology offer when used standalone or embedded in RHYTHMOLOGY.

When you download  Loop Session Series – Rhythmology as an upgrade you receive 2.9GB content that is expanded on your hard disk at 5+GB.

The main content when it comes to the size of the downloaded library is not related to to the Kontakt library (that is if you have RHYTHMOLOGY already). You receive as a bonus section audio files that you can use in your DAW without the need to load Kontakt from Native Instruments.

You can load the included within Kontakt as shown below:

Compared to the RHYTHMOLOGY your possibilities within the offered interface within Kontakt are limited. When you have the RHYTHMOLOGY product you can use this new patches within the free Kontakt Player 5.6.8, if you do not own RHYTHMOLOGY the full version of Kontakt 5.6.8 is required.

As you can see in the image below where at the top LSS and at the bottom RHYTHMOLOGY is shown there is a large difference on what you can do with the two libraries itself. With RHYTHMOLOGY you do have so many options to mangle and change the sound selected where with LSS you can play the loop and do the FX in your DAW outside Kontakt.

When you use LSS within RHYTHMOLOGY you can see the loops that you marked as fav in LSS. And you can as usually add effects. The main difference is when you have RHYTHMOLOGY that you get the included sounds/loops as wav files(5GB)

Here is a playthrough to show some of the included patches.
So what is the verdict? If you have  RHYTHMOLOGY you get Loop Session Series – Rhythmology currently at the special discounted price for 49 USD the audio files for easy use in your DAW. If you do not have RHYTHMOLOGY right now you get great loops that miss the RHYTHMOLOGY Interface to further put effects on them, however, you can do that with additional plugins (which may come at additional costs) in your DAW.
My recommendation is to rather go for RHYTHMOLOGY instead, if you do have RHYTHMOLOGY already you are not getting any new content besides the audio files stand alone which have been in RHYTHMOLOGY embedded.
 (All Links above are Affiliate Link)