40 boxes is more than enough of a chance to get a Wells. Thats around when I got mine, and I was among the first few to get one.
Its best to only open ~50-60 boxes at a time. If you don't get a ship, cut your losses and try again another day. That way at least, you don't blow 200 keys on nothing with Lobis. (Though with the Temporal Lockbox that isn't an issue like it was with the Ferengi or Tholian boxes. The Destoyer is actually worth it)
Wells, even with the Wells at, let's say 50m EC it will still take me ages to get it. But I'm patient and I remember a time when my main character already had Six Million EC. I am going to have so much again.