Dear Martin,
The last Item I mentioned was only worth £2.50 inc. post, but out of principal I wasn't going to 'let it go'. eBay had threw this partic. Seller out soon after I bought the Item so I had a good case right at the beginning!
My normal 'fields'/'areas' are 100% successful because of the nature of what they are and the sort of people selling them, however, 'general 'things' can be a problem occasionally. It's certainly better to use PayPal wherever and whenever possible, and a look at their FeedBack tells all really in the first instance - which I failed to do with the £2.50 purchase!
On the whole I think the two systems work quite well, but, as with most things, there is room for a little improvement.
Regards, Bernard