I prefer the more granular dynamic filter on model, just because some things get weird. You may accidentally pick up netbooks or iPads or tablets or ThinClients using chassis. I do computer model as we get new devices. But we have a full inventory I can pull model from, and there's only 6 laptop models.
To see model names, build a Computer Report that includes [Logical Device].[Description] and [Logical Device].[Model] for fields, then set up the Filter Expression to only include results where [Logical Device].[Description] is EQUAL to AT/AT COMPATIBLE. From there, you'll get a report of the model type of all your computer resources.
You can then build a filter based on this, where [Logical Device].[Model] EQUALS Latitude E5500, or perhaps you could be more flexible and say where Model contains 'Latitude' or 'Precision M' or 'Vostro.'
This isn't fully dynamic though, since it requires you to add computer model. But it may offer benefits above the chassis model shared above.
Can you tell I'm a Dell customer? Hope this helps you as you build your filter.