I will be selling my Audi S3 soon and am considering one of the car buying services. I got a few online estimates yesterday from Carvana, Carmax, Vroom and ALGO. I had never heard of ALGO before. They made the highest offer yesterday and texted me today upping that offer by $500. They have been more aggressive than the others with texts and phone calls, which leaves me feeling less than warm and fuzzy. So have any of you used ALGO or know anything about them? I'm leaning toward Vroom which gave the second highest offer, but at least I've heard of them.