UPDATED (see below)...
I bought this router as a replacement for the Linksys WAG160N, which had problems with overheating, as I need a stable connection to view the video from an IP camera I just bought.
I read in a few reviews of the Netgear N600 (DGND3700), the there are some issue with the connection dropping out, which concerned me a bit but I decided to go for it anyway and hope for the best.
It was delivered to my parents' house, so thought I would first configure it for their ADSL Max line to see if it seemed OK...anyway, after entering the ADSL info into the router's configuration page via the supplied network cable and getting a green light on the internet connection, I was surfing at the usual speeds in no time. I got the wireless working in a few minutes too...then...I got a red light...and the connection was dropped...I looked at the router status page and the IP address was 0.0.0.0
I was thinking of all sorts of reasons for it...could it be noise on the line, the ISP blocking my SSL port? etc, etc but bearing in mind that the previous router had no problems at all when surfing and downloading over port 443, this couldn't be it.
I looked a bit deeper into some of the issues people are having with this router red-lighting and it seems that there is a common thread. Basically, if you are on one of the older ADSL Max lines, then be prepared for patchy connections...some people are going little more than an hour, or at the most a day or two without losing the connection and having to reboot. I am on firmware version V1.0.0.12_1.0.12 and as far as I am aware, there is no patch for this connection drop-out.
The good news is that if you are on one of the newer and faster ADSL2 lines, then the NETGEAR N600 connection is stable...to test this out I took it over to my house where I am on ADSL2+ and sure enough, I have not seen the red light once...three days of continuous connection and counting.
As far as the router features are concerned, port forwarding works fine, I can access the router remotely over the internet without a hitch, the DynDNS.org updating works as expected when the IP address changes, I can access my USB drive over the internet via FTP or HTTPS, my IP camera connection is stable. The 5GHz wireless connection is fine although the range is poor...and there are loads of other features that I haven't tried yet (which I am sure you either know about or are about to find out about).
If the currently stable connection it is any different over the next few weeks, I will update this review.
So, the moral of the story...if you have an ADSL2 line, great...more than likely this will be an excellent, stable router for you...but if you have ADSL Max, then be prepared for serious amounts of frustration and plenty of calls to tech support.
Good luck.
UPDATED (7th Dec 2011)...
I noticed that there is a new article in the PC Pro magazine (issue 208) that mentions this router specifically. It seems when they originally reviewed it, they gave it top marks but then received lots of emails from readers complaining about the reliability of the connection...so PC Pro actually bought one and tried it out (- now there's a thought!)
Basically they found exactly what myself and others have been finding - that on the older ADSL / ADSL Max lines the router keeps dropping connections and can only be recovered by switching the box off and on again. The author of the article noted that things could be improved by connecting to the router via telnet and tweaking some signal to noise parameters (although he didn't mention specifically how to do this), however, these settings only lasted until the next red-light, where they got lost after a power off.
Essentially the final advice was that they would "...fully recommend the DGND3700 as a wireless router if you're on cable or ADSL2+; those of you on old-school ADSL variants are better off shopping elsewhere, or at least waiting for a few months to see whether Netgear solves the problem with a firmware..." but don't hold your breath, as the article noted these issues have been reported on the Netgear support forums since May 2011.
Since I wrote the original review I have not seen any connections problems with my router on an ADSL2+ line - in fact it has been switched on since I got it and has never failed. The only minor niggle I would have, is that the button on the front to toggle the wireless mode on/off does not always seem to work. The trick is to hold the button in for about 5 seconds, then repeat if it didn't work the first time.
Again, good luck!