Although there are some very (!) interesting libraries - I own several of them - using this sampling engine, I can't wait for them to move to eg Kontakt.
Not that the engine by itself is doing a bad job (actually, it even might include too many features), it's just that the (g)UI is a nightmare.
Looks a lot like a program written by a programmer for his/her own use, rather than one with a client (non-programmer, musician) in mind.
There is a manual (don't google it, click on the question mark right to the 5 big "tab"buttons just below the top of the window), but it's not the kind of manual that will get you up and running quickly. (as a side remark : I like to add notations / yellow mark / etc a manual while using it, you can't do that with this one since it's buried deep down in the application's package, so you better create an editable duplicate of it).
And - always a bad sign - if you look for information or tutorials either as text or as video, there is very little to be found on the internet.
Sure you can load in a library or some of it's instruments easily, but it's the steps beyond that.
Just the mixer section can provide for many hours of fruitless efforts to get it right (eg explain me why - when there is no "layer 7" in the list of layers/loaded instruments, the mixer persists in showing a layer 7 channel ...) .
Compare it to driving a car : an automatic shift car is great for most circumstances, still, I don't mind driving a manual shift car when necessary ... but I do mind having to know how to put together a gear-box myself - and not having some training material on how to do this .
PS : this is not even close to a full review - but currently prefer to spend time trying to actually make music.
PS 2 : turn of the (Engine) reverb on all your instruments - it just eats your cpu.