I don't have a long history of comics purchases, but I have purchased sports cards from Goldin. I have found their internal grading of raw lots and their auction descriptions to be problematic. It's a mixed bag for the buyer. In the positive column for buyers (Negative for sellers) they don't really tell what is in a large lot. I bought lots with short prints that were not listed, which if listed would have likely driven the price up. On the negative for buyers side is that they do not describe major flaws, even for a key card in the lot and just group the items as X grade to Y grade with some better and some worse. The some worse can include the key card in the listing, that they fail to disclose what may not be obvious in a picture. The graded items that are simple to describe don't really suffer from this as what more can you say about a single item that has a 3rd party grade that isn't obvious. The record sales draw eyes to their auctions and their history of record prices realized draw sellers, but I feel like they have a lack of interest in improving the listings on the meat and potatoes. If they can brag about record setting prices on a handful of listings, then the higher ups are probably satisfied. It has not been my favorite auction experiences though and I rarely utilize their platform. I imagine the first submissions of bulk comic lots or raw copies will get higher attention, but with low experience and that any raw lots will be a similarly unsatisfying experience where nothing raw is graded properly or described sufficiently.
I am used to the model of having one end time for the auction and then extending on either a lot by lot or whole auction basis. The auction houses that extend the entire auction if a single item gets a bid can be incredibly frustrating. The other ones where each item gets its own timer once a bid is made tend to allow me to make decisions on lesser tiered items if one of my main interests goes out of my price range. The item by item live bidding on Heritage just takes too long to get to books if I am interested in Justice League or X-Men.
Just my 2 pennies based on purchases from Goldin.