It's a pretty good platform, maybe because of the ratings system.
For that reason, expect people to be a bit suspicious of you if you haven't yet bought anything. It won't be personal (and it might not happen), so don't take it personally.
Generally, I ask questions before bidding. If there's almost no time left on some auction, let it pass. It's not worth the buyer's remorse. Buy only what you want and know you want. People don't mind if you ask for more pictures. Sometimes there is a bit of wait, but no big issue as it is expected if you're a seller. If the seller gets defensive when you ask for pictures or more info, then move on, he or she is probably a prom queen who will make your life miserable.
Also, I only bid what I want to pay. Don't get sucked into that one special item... There will always be more.
In fact, I've found that unless I'm bidding on something made of unobtainium, I am better served to let a few auctions go past to see what people are willing to pay.
happy collecting.