Lately there are very few bidding wars, most things sell for the asking price if they sell at all. Lots of stuff way overpriced listed by non-collectors or just wish full thinkers so there's obviously less people browsing. Personally I've had very poor results selling there over the past few years and now sell mostly on Delcampe.com, a website much like eBay in it's early days but caters specifically to collectors with slightly lower selling fees. But most things there are listed individually, there are very few collections or groups of items. Unfortunately there's low interest in higher value items.
With all the recent changes to eBay, and more coming, it makes selling on eBay pretty risky at times.
Plus you'll notice there are typically only 400-600 items listed at any given time on eBay in the slot card category these days where there used to be a few thousand at times a few years ago. For comparison, there are over 15,000 slot card listings on Delcampe currently.