Scheduling with Auctiva is free. eBay charges $.10 each time, I think. Really, it's not much of an issue. I have had times where my listings have not shown up in searches as much as 12 hours after posting. Of course, this is not Auctiva's fault. My listings usually show up in searches pretty quickly.
I'd always assumed that eBay's scheduling feature suffered from the same "indexing" lag, however, I've never used it before, so I can't say for sure...
Personally, I'd rather suffer the occasional lag than have to pay a dime every time I wanted to schedule an auction.