I've been using DesignSpark for over 1 month now: It's quite capable and for a free application it's amazing; however, here's an issue I ran into that's handled better on other PCB programs and would be great to see in DSPCB:
Currently, DSPCB shows a schematic and its associated PCB within a single window area (in programming parlance this is referred to as Parent/Child windows; such window relationships are common for example in Microsoft WORD and many other Windows programs); Although it is possible to view both a schematic and PCB side by side using Window -> Tile Horizontally, or Window -> Tile Vertically, or just clicking the Schematic or PCB tab as necessary, regardless of which option you select, both the schematic window and the PCB window area will always be restricted to the maximum area of the main DSPCB window. With this behavior it's best to have as large a monitor as possible to maximize the view when using either Tile Vertically or Tile Horizontally. However, some other programs allow you to "undock" either the schematic and/or the PCB window so that if you have multiple monitors you can move one of the windows to the other monitor - such an arrangement is more productive: 1) You can see both the schematic and pcb in atheir own window simultaneously. 2) Any DRCs you run can be more easily cross-referenced. Although many users will not have a multiple-monitor setup, it is not that uncommon and it would be great if DSPCB allowed for undocking of the schematic and PCB windows to take advantage of multiple monitors.