The seller has got a fairly good record (though have a look at the comments - a high number of non-deliveries!). As he allows himself a long time to post you might not have it for Sunday. But would go with starshakers suggestion as well.
It looks okay, but on his feedback there is one person accusing him of selling a copy of Band of Brothers - he replies that it comes directly from the manufacturer in Hong Kong (hence the slow delivery times) but is deffo not a copy. I don't know - if it is a copy (whatever that is) it'll probably be a good quality one. His feedback is pretty good all in all, and that would be convincing enough for me.
It does state on the description that the film is sealed, so it would be a blatant lie if it weren't.
I looked at the previous buyers comments bit - a lot say "delivered as described" or "arrived fully sealed" - there seem to be quite a few that say "lost in post but refunded quickly".
I would say that it is as safe as you are likely to get through ebay but there is always a small risk. He does have a 98.5% positive feedback rating though and you don't get that by ripping people off. Plus over a 1000 previous sales.
I think getting people for false advertising is pretty tricky on ebay.
Several of the comments say the DVD is posted from Hong Kong, which is where lots and lots pirate DVDS come from. It's strange that the DVD is Region 2 + 4 only, though - I'd expect pirate DVDs to be regionless, IYSWIM. Also, it says: "PACKAGED IN A SINGLE AMARAY CASE. NOT A DIGIPAK OR TIN BOX ." It does say 100% original, but I'd expect this to be a copy.
I agree. Would doubt it would be a copy from somebody that has such high feedback. My personal experience though is that sometimes the people with massive feedback can get a bit 'over-run' with orders and can take a while to deliver - even sometimes not sending items (probably genuinely forgetting), but always apologising and resending when queried.
Seems a bit strange that so many of his items 'go missing in the post'.