If you want wet dry then you'll need George not Henry.

I sell George and Henry machines to Motor trade for valeting. They run all day none stop and they are tuff little buggers has well getting crushed by numpty valetors with vehicles all the time and still carry on working.
Plus they have good spares Backup and you can buy just about any part for Nuematic machines. They will last years if treated nicely even when running for extended periods.