Unfortunately, my copy is also very slow when loading. Reading is ok. However, it crashes a lot and scrolling through the page number takes forever.
Maybe it's the software. Anyway, https://www.dibizentral.ch (Onleihe) told me that Tolino is currently having problems.
In the meantime I have got used to the slowness. (Every mobile phone, and I mean every mobile phone, is faster).
F. Egloff

It seems to depend on the book you want to read. I only lend books via onleihe. Some are very slow, then ok again after restart. Definitely not fast, but reading is not a hectic process. Errors that don't allow the book to open are much more tedious, and that's probably not just specific to the e-reader.