I have one of these now and a 2nd coming that should soon be shipped. They are very flexible in configuration, with no fans and are an excellent choice if you want to power multiple boxes with a great lps.
They do a manufacturing run and then sell/ship until they are all gone and then queue up another one and often additionally upgrade the unit with improved components. Because of this there are windows (sometimes long) where there are none available. They are just getting new units in from another manufacturing run and will soon start shipments. This unit was also improved with a bigger heat sink for the rectifier.
When they have availability they ship on a first pay first served basis. You can, as a previous poster said, get your name on the email list to be notified when units are available, but if you want to be guaranteed a unit, email them telling them you want to prepay and they’ll send send you a link to pay. That gets you in the guaranteed ship queue, That’s what I did. IMHO, I would have no concerns about the unit or company.