In the countless dozens of orders I've made to Magic Madhouse, I've only had one issue, where they sent me the wrong play mat. Other than that, they're excellent. If it's just singles they send it in a jiffy bag, and also in wrapped to a toploader for sturdiness. Any foil come in clear sleeves to stop them from scratching in transit.
I've only had a few orders with Chaos Cards, since their stock levels for singles are generally non existent (excluding some Pauper playables), but they're service is on par with madhouse.
Bigorbit cards on the other hand I've placed a lot more orders with than chaos cards- they generally have what I'm looking for if Madhouse don't. However, I mainly order EDH singles through- I wouldn't recommend looking for playsets on their site, unless the set has just been released. If anything, I think their service is much better and you get your cards much faster (about 5 working days for Madhouse normally, and 2 to 3 for bigorbit). That said, you can't actually filter their singles when searching, and there's no option to just look at what they have in stock.
July 23, 2018 6:33 p.m.
I have a preference for Magic Madhouse, I've found Chaos Cards customer service to not be as hot. But they are much the same in terms of shipping, packaging, price for the most part so if one has what you're after it can't go too badly wrong