Does anyone have any experience of buying "discounted" items online? What was your experience like?

I'm considering buying a silver GBA SP off the website because none of the stores near me have them in stock, but I'm just wondering what others have experienced when buying "discounted" items off the website, given there's a £20 gap between the two versions. I've bought discounted items in-store before with little issue, fixing a Game Boy screen with a quick fix is the most I've ever had to do, but is buying online where I'll have no chance to actually look at the item before it arrives a significant issue? Am I overthinking this?