I'm using Minoan to furnish a luxury STR and it's been incredible, and I am actively trying to find a way to better leverage their service. Yes, it's true that you might be able to find a product you need at a greater discount when a brand like Wayfair or CB2 is having a sale, but I've found that they truly do offer superior discounts at scale, even considering the fee.
What I find to be most valuable: Ease of use, cost-savings and efficiency and here's what I mean: If using an interior designer to furnish your rental, they will hand you a list of supplies + furniture to buy and what I was able to do with Minoan is upload that list as a CSV file and then they come back with a quote of all of the items they can fulfill along with their respective discount. My EA and I were able to validate that the discounts provided were better than anything we can find on our own and if you think about it: Instead of going directly to CB2, Wayfair, Rejuvenation, West Elm, etc., you can just buy it all in one swoop through Minoan.
So yeah, my experience has been outstanding and they customer service has been exemplary. I specifically want to call out one of their Senior Accounts Associate, Charlotte Cunningham, who helped me through the process on my first purchase as I needed to buy a sizable amount of furniture quickly and she was able to help me make moves quickly...and didn't make me feel bad whatsoever when I pulled back a few items at the last minute I was able to find them cheaper elsewhere. Left me feeling like a basically have a retail/fulfillment person on my team so I'm a big fan and would recommend giving them a shot, especially if you're in a similar position as I was: Needing to furnish an STR quickly and cost-efficiently.