Can you use two separate snipe sites to bit for an item on e-bay?

Hello John,
Thank you for your question about using two snipe sites. If you place more than one set of bids, you risk bidding against yourself. For more information, see this link on our site:
https://bidslammer.com/help/bid-against-self
Thank you for taking the time to write in. Please let us know if we can provide any other assistance.

What is the time frame when BidSlammer places your bid? Is it 10 seconds and, if so, Why 10 seconds?

For the free service it is 10 seconds. You can upgrade to bring it down to 1 second.
If you are bidding on Rolling Stones tickets, we add extra karma. :)

So is 1 second better than 10 seconds? I have read that 6-8 seconds is best. Please clarify/.

last question:
I bid on an item & when I look at my bid it says Current (1), but when I click on it, it doesn't show any item I bid on?

If I log in as you I can see 1 snipe under Completed. Perhaps if you refresh the page it will show?
Opinions vary on lead time. I don't think it matters here because, at the risk of sounding cynical, I don't think you will win Stones pit tickets for $425. Those retail in our city for $995.
In general though, we have a detailed help page to help you decide:
https://bidslammer.com/help/minimum-bid-increment
Good luck!