I can't say I've ever paid that much attention to all of the aucitons that SlotsUSA runs since they end at the same time. However, not really being in the market for a new machine myself I decided to watch all of them to see what happened at the end.

10 Pachinkos were being auctioned this evening.
5 of them were sniped or at least bids placed at the last minute.
"Original bid" is as of an hour before the close of the auction.
For ease of understanding, I'm going to list the eBay name.

Bruce Lee
Original bid - 6
Ending bid - 6
Won for $248 by sierramadrecollectibles who was in a bidding war early on with electricblond on a number of auctions

Mozart
Original bid - 12
Ending bid - 12
Won for $152

Rose of Versaillies (Sniped)
Original bid - 9
Ending bid - 11
Won for $178

Rescue Dogs (1 bid snipe)
Opening bid - 10
Ending bid - 11
Won for $243 (Can someone please let me know why this pachinko is going for so much??)

Monkey Magic
Opening bid - 7
Ending bid - 7
Won for $167

Lord of the Rings (1 bid snipe)
Opening bid - 17
Ending bid - 18
Won for $321 (price driven up by sierra and electricblond)

Fever King (1 bid snipe)
Opening bid - 16
Ending bid - 17
Won for $141

Popeye
Opening bid - 8
Ending bid - 8
Won for $305 (Sierra won this one too, only electricblond bid and none since 5/1)

ET
Opening bid - 11
Ending bid - 11
Won for $138

RoboCop (1 bid snipe)
Opening bid - 24
Ending bid - 25
Won for $255

So of the 10 auctions only half of them were sniped and only one of those 5 had more than one bid placed at the end.