Have owned the 3500STBII for over a year now, so time for a brief review:
USB port issue solved with use of USB extender cable, so not an issue any more. Power supply issue (eventually couldn't power my 2.5" USB powered HDD) solved by using an externally powered HDD. The "improved" remote of the 3500STBII is solid and works well. So what are the remaining issues? The power supply appears to be degrading over time, as now the recorded picture shows signs of "dimming" and even dropping out occasionally implying the PS may not be optimal. Getting to the point where picture breaks up (NOT pixilation, as the RF signal is solid), drops out, tears/smears more than a few times in a 1 hour recording. I suspect that the lifespan of this unit may be in the 1-year category. Probably a good time to start looking for a replacement DVR (possibly the Homeworx HW-150PVR or something similar).