For offline rendering polygon count doesn't mean much - as long as its not ridiculous like it has 200,000 poly screws/bolts.
For real-time its more important, but again its more specific to the required format. Using LODing for low poly is a good idea for your customers so they can choose which Level Of Detail they require. If you have a (0) 10,000 poly (1) 25,000 poly and (2) 100,000 poly version of the same model then the customer has a better choice for their workflow.