Hi Mike, in answer to your question, any CRM that is compatible with mobile safari and can bring up a PDF preview *should* be able to use the printing functionality. The main problem is speed. Accessing web CRM's through mobile safari is just so slow.
Now, if you are wanting a native iPad app that was built exclusively for the platform for speed, etc. then you will want an iPad app that is not web based. I am not sure if the dealer.com iPad app is a native app or just web based. It does make a huge difference in speed and being able to access your data offline.
If you get a moment after visiting dealer.com's booth, feel free to come by our booth and check out our iPad app as well (don't worry - I'm not a sales guy - I'm just one of the developers)
Hopefully, one of our solutions might be able to meet your needs. If you already have a CRM you like, feel free to come by anyway and I can show you how you might be able to print from safari from your current provider. Just look for the auto accelerator booth. Let me know if I can be of any help!