Not really. I was put off by the fuzzy nature of SH3's appearance. It just doesn't look very good when your native monitor resolution is a lot higher then the games. I think id like to fondly remember the game as I played it on my CRT , and not as i saw it on my LCD last night. (That and i have an idea on another project

)
edit: It does occur to me though, Dat files are not downward compatible. (in a drag an drop sort of way) Meaning, SH4 can read and understand everything from SH3. But sh4 adds new stuff, stuff that SH3 can't read or understand, hence the barfs to desktop.