@ProgeGames While the following text will probably not add much information, we can only say that it unfortunately really depends on your use-case and needs to be measured on your target device. You need to take into account how many vertices, bones, constraints, draw-calls per skeleton (due to multiple atlas pages), and so on you will need for each skeleton. Regarding draw calls it's also important how many different skeletons there are, whether it's 30 different skeletons or 5 skeletons of 6 skeleton types (all sharing a single atlas texture and material), with the latter leading to fewer draw calls.
You can have a look at the Performance section of the spine-unity FAQ to get an idea of what might be more costly, so that you can test with skeletons that yield measurements as close to your final assets as possible.
Of course, we're always happy to hear from real-world cases, if anyone wants to share their experience regarding their game. The Showcase section of the website shows what existing games have achieved using Spine.
