I have looked at both auctions and nothing strikes me as "irregular"
Taking the second first.
This looks absolutely genuine - an item highly competed for. Sixteen or so bidders makes the risk of any type of "ring" very remote. If you look at the "underbidder" redz1940, he looks 100% genuine - he has chosen an "odd" amount to try and second guess his competitors (as you should - see my earlier thoughts on this subject)
If anything it confirms what you must have thought when bidding, that the current price level for this item is more £700 than what the others generally thought (around £500)
My other thought is that they were perhaps commercial buyers hoping to make their "turn" and that just left two genuine private buyers willing to pay almost "retail" prices.
The other item is much more difficult to assess - only 3 bidders (indicates a very narrow market) and two of you very close. The other bidder has also hidden his feedback which makes it impossible to see what else he bids on.
If he is the underbidder frequently (or conversely "pips you to the post" frequently) my guess is that he may be "marking" you and noting what you pay.
I collect old cameras - some extremely obscure and the literature is now quite valuable. I know that there are five international buyers in the area I am interested in and I can almost - but not quite - guess what they will bid!
Perhaps the best illustration is Schneider Trophy memorabilia - I will bid very highly for 1931 and only 1931 (my Uncle won that particular race) items. There are two others that will do likewise. In the end, we can ignore the rest of the market for we three practically determine it! (I note with concern a new entrant who pays double current prices - you have to notice these things because it influences your own bidding level!)
Is this likely in your case?
I am absolutely satisfied that AS is secure, if that helps. Its just that collecting anything does lead to paranoia at times!
Paul
The first auction