The included Windows software seems very ropey indeed, scanning 28E yeilded hardly any channels at all, no lock at all on "known good" transponders, but under Linux using the linuxtv.org LME2510 DM04 drivers (the tuner chip is the M88RS2000) it happily tuned to any DVB-S frequency including switching a Diseqc 1.0 switch between 4 LNBs. The driver sets the box to send the entire transponder to the computer and it demuxes in software, meaning that you have the flexibility to record all the channels on a transponder if wanted.
The Linux driver requires a very recent 2.6 Linux kernel, more recent than those shipping in any of the current distributions I've seen, so be prepared to build your own one. It is also necessary to download and build the latest LinuxTV drivers, and to install the Windows software first to be able to extract the firmware needed under Linux.
At £16, a bargain, under Linux at least.
(Additional: now also working on Raspberry Pi, still no reliability problems using the rpi-3.6.y kernel branch at github, except for the occasional glitch - this doesn't happen when used with Linux running on a PC)