Dimension Modelling Senario Data Warehouse Design I'm looking for some advised on how to model the following scenario in our data warehouse. 

We have the following entities


Staff 
Mobile Devices
Computers
Mobile Bills


If feels like its simpler to model without fact tables for Mobile Devices and Computers, because essentially there are no measures, Option 1 shows this. Option 2 shows the use of Fact tables.





What's would your advise be on the best practice in this scenario? Any input would be appreciated, thanks.
The second version looks more realistic. Mobile devices and computers can change their users and this version allows to keep the history.