My 2 year old 56' is, indeed, a Sammy but I have experienced none of those issues ... maybe my 56" does not qualify as a "larger DLP model" like your 61"
Granted, most people who buy a TV probably won’t have major issues, or any at all (I have a Sony CRT I bought in ‘95 I think that’s still going strong, despite 4 moves in that time). Just with the number of people I noticed with this issue, I thought it worth mentioning. And by no means is 56” small. =)