well I guess it being worth it or not would depend on your view of $100 difference in price.
When I've got a lot of torrents going, my torrent program will use up a lot of RAM since it's trying to write and seed all those files. I've actually had to set my computer back at stock PC3200 settings because my RAM had been acting up and I dont have time to RMA them again, however it annoys me not having it running at 250MHz DDR500 like it used to. Photoshop was much quicker even when torrents were using my RAM resources.
I don't regret paying the extra cash for good RAM because I wasn't looking for just an increase in games. I also wanted my normal programs to function faster and they do.
If you want a noticeable difference you'd probably want atleast 230MHz, but you probably wouldn't think to yourself "Hmm....my computer responds pretty good now" until you hit around 250MHz, but that's just me........by that point on an AMD64 system you've gained a lot more mb/sec bandwidth