I've used Scancafe to scan a couple of orders of negatives so far. They run various sales almost every other week or so, so the prices can easily end up being about 20% or more lower than what they have listed on their site. They do ship your stuff to India to do the scanning (you can pay more to avoid that). I've been satisfied with what I've gotten back from them. I wouldn't be surprised if they put their value packs on sale on black friday, they have in the past.
I actually bought a Nikon Coolscan 5000 a while back that I'd started to do this on my own. After some initial work to get the right settings, the results were good, but the process was time consuming and tedious to say the least. The plus was I got a higher dpi scan than what scancafe provides unless you pay extra (their default is a jpg at 3000 dpi, you can pay more for tiff or 4000 dpi scans). I need to get around to selling the Coolscan off, these days it's actually worth more than it was when I bought it.