The DGN2200's build quality is very good, and it's aesthetically pleasing to look at. It's petite - smaller than early DG834s - and easy to set up. I'm no longer disappointed that I missed a few Billion BiPAC 7800N's on ebay over the past couple of months.
I bought one because it could be wall mounted, has a familiar interface and easy-to-use built-in guest networks so visiting family members can use their own security mode.
The DGN2200 is like earlier versions of the DG384, with the same familiar interface plus a few new settings. Performance is about the same here, with synch speeds roughly 2 to 4 megs below the advertised limit for my Orange line. The only noticeable differences: line attenuation dropped from 39.5 to 38.5, and it runs cooler than any of my 3 previous Netgear 834s.
Then, and this is the clincher... I discovered the Modfs project on Sourceforge [...]. The two files for the DGN2200 are found at the bottom of the download page, under Modfs 0.2 beta release: "modfs_image-0.2_beta.zip" and "World Wide Annex A". This free firmware can turn a DGN2200 into a THOROUGHBRED (there's firmware for the DGN3500 as well). Within two days of tweaking just a single parameter, my speed went up to 9,510 kbps and, so far, has stayed there. The first file contains the bulk of the firmware; the second file is a modified Netgear firmware.
I'd never risked custom firmware on a modem/router before in case anything went wrong and recovery might not be possible. The Modfs firmware is not like other custom firmware. It is not a complete replacement; it's one file on a USB stick in the socket on the back of the DGN2200 (and in my opinion this is by far the best use for that socket, all things considered).
There is a firmware update to perform (the link labeled "World Wide Annex A"), but it's mostly original Netgear firmware (v188.8.131.52), slightly modified to make the DGN2200 boot the .bin file on the USB stick, the file un-zipped from "modfs_image-0.2_beta.zip."
After a re-boot, use "192.168.0.1:8081" to access the new Modfs interface. (The password is easily guessed.) You can still access the DGN2200's Netgear GUI, too, at 192.168.0.1, and you can have both GUIs open simultaneously.
The main setting of interest in the new GUI is on the Setup page, Main tab, and it's called Target SNR Margin (%). Try working your way back from the default 100% in cautious steps over a period of a few days, ideally making changes at times when web traffic and noise levels are low, and with luck you could be in for a few surprises. After my last tweak, my DGN220 actually went up from 8832 overnight to 9510 the next morning, and this on a line with a history of instabiity. It's an Orange up-to-9 Meg package with 5.5 to 6 Mbps available according to line checkers. Immediately before this new firmware the synch speed was 5,868 Kbps. We're about 1.7km from the exchange, and our phone line and box are the same ones that were here when we moved in in 1980. Our phone went out catastrophically twice last year when Open Reach botched some connections in the town centre.
You can run your DGN2200 without the USB stick as a standard DGN2200. The Modfs BIN file can be updated without needing to flash any firmware. You can disable the Modfs firmware completely by flashing official Netgear firmware and you can still reset the DGN2200 to factory defaults.
The only other changes I made to the Modfs defaults were to clear the Annex M, G.lite, T1.413, and Re-adsl2/2+ boxes under Adsl Settings > Modulation, ticked Bitswap and SRA (Seamless Rate Adaption), and ticked the Kill Email program and Kill DDNS program boxes just for the heck of it.
A few of the many other new features available in the Modfs firmware are a full-time Telnet server option(!), LAN, WAN, and WLAN monitoring graphs, and even a Linux package manager. There is a Retrain script, but I could not get it working right. Maybe I just need to find the right inputs - it kept re-booting the router.
As I write this, the line has been stable for a week at the highest synch speed I've ever had. My downstream Noise Margin has been between 4.8 and 6.8 dB - lower than it's ever been by a about half. And there is still room for further experimentation in the Modfs GUI. It's been a revelation.