I just recently purchased this STB (assuming you mean the DTB-H550F) along with the Samsung LA32R51B LCD Panel. I initially had a problem where I couldn't receive Channel's 7 or 10 in either SD or HD with the STB. I started a thread in the 'reception' section of this forum (
here), and after some advice tried a Factory Reset of this STB which fixed the problem.
So, given I've only had this STB working properly for one evening, I'm hardly the best resource to go by, but I can definately say it works, works well, looks good and when you get a Samsung TV as well it means you only need one remote for both devices ... very handy that

P.S. the problem with the factory reset might be that I got the STB off eBay. I've no idea where inthe world it came from, but given I paid $220 for it brand new (as opposed to the $500 it seems to retail for), I can only assume it bypassed some points between factory and me. This may have added to my set-up woes initially ... perhaps.