Twitch live viewers are the one service on this list where timing beats volume. A stream that already has people in it holds the next person who arrives; an empty one loses them in seconds. That means the order has to be placed for the opening minutes, and it means a seller that cannot start on demand is useless to you no matter what it charges. Confirm the start behaviour before you buy, not after.
Twitch is a live platform, so the number that matters exists only while you are streaming. Concurrent viewers decide whether the directory surfaces you at all, and they decide it in the first minutes of a stream when a real audience has not arrived yet. Followers are the durable number and the cheaper one; viewers are the one that changes what happens during the broadcast. Twitch's own rules on view manipulation are explicit, and viewbotting is the specific thing they enforce against — pacing and a plausible ratio to your follower count matter more here than on any recorded-content platform.
Beyond the metric itself, the same four things separate a working order from a wasted one, and none of them are visible from a landing page. First: whether the seller asks for your password. No legitimate provider in this category needs one — a public username or a post link is all the work requires — and a request for a login is the end of the conversation, not something to weigh against a lower price.
Second: whether the price you are quoted is the price you pay. Retail sellers here quote packages and panels quote a rate per 1,000, and the gap between them once you normalise is routinely fiftyfold. Every figure on this page has been converted to the same per-1,000 unit for exactly that reason, and the spread it exposes on this service is wide: $14.99 per 1,000 at the bottom against a median of $33.80 per 1,000.
Third: what the refill promise actually says. "Refill guarantee" is a marketing phrase until you read the window, the trigger and the process. Thirty days, automatic, no receipt required is a real guarantee. Thirty days, on request, subject to review is a support ticket you will probably not bother to file. Fourth: whether the seller has been trading long enough to still exist when you need the fourth one. Domain age is on every provider's page here, and it is the cheapest signal in the category.