Have the Zmodo. Paid $229 on eBay with 1TB drive. No issues, works great. Can't really complain given the price point.
Poorly written manual. Chinese to English translation issues. Mostly irritating. There are some YouTube instructional videos online.
I'm using my existing 14 cameras with the Zmodo. Mostly Sony cameras. My old DVR got fried due to water damage from a mechanical room leak, so I have my old cameras. Image quality as good or better than my old $800 DVR.
Count on calling customer support to get remote viewing to work. On hold for 90 minutes, but they were courteous enough. For dynamic IPs, they say to use Dydns free port forwarding service which is preconfiguredin DVR. Beware effective Dec 2011, it is no longer free service. $20/yr or $80/5 yrs. Using free Asee+
App on my iPhone for phone remote viewing - no issues, easy to use. Zmodo customer support help me set up the iphone as well.