What I like best about Onshape is their approach to content creation. It is a tool designed to capture design intent. I came from a SolidWorks background which I really enjoyed using, but when I started contracting my work I needed a CAD solution that was a better fit for a one man operation. I started my trial trying to use it like Solidworks and quickly found that Onshape had a different approach. After I finished the beginner tutorials I quickly realized what they had done to the design process. After I used it as intended I saw the light and really liked they way they create content compared to how I used to do it in Solidworks and other programs.
Configurations are done exactly as they should be both on the part level and assembly level. No endless tables of permutations, just the things you want to change.
Another huge plus is the PDM system in Onshape is absolutely amazing and simple to use. Since it operates in the cloud there is no server maintenance, server connectivity issues, or install issues.
Onshape has also shown me how awesome it is to never have to save. All changes are documented and having the ability to version and go back in time to what was done is something that nobody else does.
Since Onshape is always releasing updates every ~3 weeks it is always improving. That being said the dislike pile gets shorter with time, but until the issues are addressed we make do until those requests get answered. I have documented my complaints with Onshape and they are all improvement requests at this time. My biggest dislike is that the drawings in Onshape are a little behind the rest of the offerings I feel.
Chamfers have to be manually entered, which breaks the parametric relationship if you change the chamfer size.
Broken views are broken. Once you break a view it no longer aligns to the related view. Annoying but usable. Section views also cannot be broken, so if it doesn't fit on the page then you have to shrink it or make a bigger drawing.
There isn't a devoted weldment tool, however there is a feature script that works pretty good, but it can be cumbersome if you are generating new profiles and can turn into trouble shooting code in the script if you make a mistake. A devoted weldment tool with the Onshape touch would be great when they get to it.
A center of mass icon for assemblies and parts is really important for a lot of designs. It seems like CM it is already in Onshape but isn't able to be used for design purposes.
Section properties would be very useful but as of now do not exist.
Like any program it is a tool, and if you want to get the full capabilities of this program everyone using it should go through all the training and practice creating content. If you teach yourself how then you will see many benefits.
Storage of content is not an issue anymore. I don't have to carry around my customers data and hope it doesn't get lost or damaged.
Sharing content is super easy now and customers really like that they can view their content from a link and export if needed. They do not need a seperate tool installed just to view the files.
Release management in Onshape has really helped with the design flow with my customers.