Thanks for your posting and considering Aspose.Total.
Aspose.Total for .NET is much more flexible and feasible than Aspose.Total for SharePoint and contains much more features. Aspose.Total for .NET is set of Aspose .NET Framework assemblies that only need .NET Framework to run/execute. You can use them in any environment like exe, dll, sql server, web service, windows service, asp.net, sharepoint etc. However, you will have to write your own code to integrate or make use of them in different types of environment.
Aspose.Total for SharePoint is only specific to SharePoint environment. You cannot make use of it in dll, exe, sql server, webservice, windows service, asp.net etc environments. It is tightly integrated to SharePoint only. Also, it has much less features than Aspose.Total for .NET and basically it is a converter that convert SharePoint documents into PDF or other formats.
Yes, Aspose.Cells for .NET should work correctly with SharePoint (some customers are already using it in SharePoint environment) but you will have to write your own code to integrate it with SharePoint environment. If you can write such a code, then you are good to go with it.
We will suggest you, you try both (Aspose.Total for .NET and Aspose.Total for SharePoint) in evaluation mode without any license and check the feasibility of both of them as per your needs and then make a purchase decision.
FYI: Please note both APIs work equally well in Evaluation Mode just like in Licensed Mode except with one limitation that in Evaluation Mode, they create documents with Evaluation Warning. Besides you can also request a Temporary License from Aspose.Sales team which will work for one month to test the APIs in Licensed Mode.