First impression: The DS-404 comes like a full commercial product: an own CD including the program files (mac/pc), manuals as PDF files, and tons of ready-to-go soundfiles.
Installation: As I like it best: a simple DLL to drop in your VST folder.
Starting the Sampler: Well, to me, the UI isn't self explaining. Loading Patches is easy, but if you start creating your own sample-sets it's strongly recommended to consult the manual, or - even better - the quick step-by-step introduction in the CM-journal.
Handling: The system of four buttons with changing meaning is somewhat confusing. I'm badly missing keyboard control and sometimes I instinctively tried to press a F-key on my computer-keyboard. OK, it's just a question of habit. But sometimes it's annoying. E.g. you set a new keyzone for a sample and intend to delete it. Then you have to leave the keyzone-mode first by pressing the OK-button before you can delete the last active keyzone by clicking F2. But that's of minor importance.
My personal PRO's: + Full-featured with keyzones, Layers and Multitimbral facilities + Small and reduced to the necessary functions + Single outputs + All-in-one fileformat + Simple and effective loop-mode
No "CON's", but rather "wishes": - Sometimes hassle with handling (function-buttons) - No request for saving of changed patches when closing the instance of DS-404 (!!!) - Arrow-Mousepointers when changing the keyzones (compare e.g. mousepointers on changing System-windows)
What could I finally say? I've ever dreamed of a small but powerfull sampler-VSTi. 3S and Helios were too simple, VSampler, HALion, EXS, Kontakt, etc., were too overloaded with features I didn't want. And now a well-designed piece of software is available to everyone for a sensational price. Grab your copy! :-)