e-Buyer, dabs, Scan etc are all excellent at delivering what you want through their couriers in remarkably quick time.
The real problems arise in the event of goods being faulty or proving unreliable. That's when the fun can start in trying to return them or obtain replacements...:-)
Much of this arises because of the sheer volumes of orders that these firms undertake in the course of a day, week, month or year. Great when things go right, but not so wonderful otherwise.
But I still have no qualms about ordering from any of them...:-)