@eeyoresmom, hope you had a great trip. Here was my experience w/ PPDG and
Best Buy. Had $300 in Ebay GC ready to go when 5x came around, so I bought $300 in BB from PPDG. No issues going to the store and converting, but it took me quite a while (30+ mins) to check out effectively w/ PPDG. Kept having me verify my phone number and all that. Later in the evening I tried to purchase $200 in SW gift cards via PPDG. It locked my account and took 3 phone calls the next day to get it working again.
That being said I never ended up purchasing BB gift cards with the remaining $600 in Ebay cards I have. Pretty frustrating because my account kept getting locked. I was comfortable taking $300 in to the store, but I think any more than $400-500 and I would be a nervous wreck. That's just my personality, though!

We only have 1 BB in town so I don't want to ruin my reputation there already!