There's quite a bit of context below, so here's the short version before we get into the story here: If you're purchasing a Sprint Treo Pro from anybody not named "Sprint" or "Palm," you should take steps to ensure that the device is running the official 1.04 ROM before you lay your money down.
In several threads in the TreoCentral Treo Pro Forums, there is much discussion going on surrounding ROMs. More specifically, many Sprint Treo Pros purchased appear to be running the pre-release 1.03 ROM instead of the final, 1.04 version. You can check your own ROM's version by going to Settings -> System -> About and tapping the Phone tab. The 1.03 ROM, while very similar to the final, 1.04 ROM, is not technically the final, shipping ROM. The differences between the two ROMs are discussed in this thread, but the main difference is that 1.04 has 2 more megs of Program Memory. Most users may not notice any changes at all.
For now, the most important thing to remember if you're purchasing a Treo Pro off eBay or some other non-official outlet is that you need to make sure you get proof that the device is running 1.04 before you purchase it. Contacted for comment, Palm stated that the primary point of support for any Treo owner should be where they purchased the device. As of this writing, Palm is not offering a ROM upgrade from 1.03 to 1.04 to Sprint Treo Pro owners. However, at least one TreoCentral Forum member was able to get an upgrade to 1.04 by taking a Treo Pro into a Sprint store.
More alarmingly, some owners are being told by Palm Customer support that their Sprint Treo Pro has been 'flagged' as "Zero Day Warranty," meaning Palm is not able to warranty the phone or offer support for it. Centro85 describes one such conversation:
After being on hold for about 5-6 minutes, the lady came back on the phone. She said the serial number is flagged in their system as a 0 day warranty. She tried to tell me this meant the phone was a used phone. I told her the box was sealed, and when I turned on the device it installed the operating system/software etc. I than told her I thought Palm had a warranty anyway, so even if this was a "used" device it wouldn't matter. She told me they can't do anything more without a new device and a new serial number. I asked her to email me a copy of the "recall" so I can get a new phone, and she told me the best she could do was give me a customer support claim number that I can give to the retailer, so the retailer cannot deny the problem and swap it out with a new device.
You can find details of the issue in "Don't Get Stuck (Treo Pro Unauthorized Release) and "Ebay Sprint Treo Pros may be Flaged!." As you may recall, Best Buy initially sold many Sprint Treo Pros before the official release -- these Treo Pros had the 1.03 ROM on them. However, there is additional speculation that the large number of Sprint Treo Pros on eBay right now indicate that many are coming from other channels.
Again, the bottom line here is that before purchasing a Sprint Treo Pro from a non-official channel, you should take steps to ensure that the device is running the official 1.04 ROM. If your Sprint Treo Pro is running 1.03, you may want to consider contacting the seller to arrange a return or exchange.