I took the numbers from a Technolawyer post. The breakdown for 25 users is as follows:
| Item | Worldox | iManage | NetDocuemnts |
Base Software Additional ServerMaintenance (5 yrs) Implementation (Install + Training) Web module (5 yrs maintenance) PDA module (5 yrs maintenance) Local replication of data Document Upload | $10,000 N/A (not needed) 10,000 17,500 1,779 1,800 N/A (included) N/A N/A N/A | $9,950 5,092 15,090 25,000-35,000 10,383 8,860 4,385 4,385 N/A N/A | $64,410 (5 yrs) N/A N/A 1,800 N/A N/A N/A $7,500 (5 years) $0.2/page =$20,000 for 1,000,000 pages (or a firm could do this themselves) |
Some of the imponderables that the user asks for are hard to quantify because they relate to ease of use and the ways in which a firm uses its DMS and its specific needs. However, based on my experience and speaking with other consultants, some things are pretty clear: iManage is going to be by far the most expensive to maintain in terms of administrative time (not to mention the fact that the future of iManage is somewhat in question since its acquisition by Autonomy, NetDocuments probably the least expensive. The same goes for training and other ongoing costs. However, it would be a mistake to think that NetDocuments has NO administrative costs. Somebody has to do configuration, new users, training, etc.
The argument concerning the Present Value of the monthly sum vs. paying a big ticket up front is a reasonable one. However, there are also leasing options by companies that specialize in leasing to law firms (such as Baytree Leasing), which let you lease the software (and consulting time) for a 3-year period and own it at the end of that time. This could have tax advantages (check with your accountant) and based on generic numbers I got will turn out to be less (possibly substantially less) than the NetDocuments cost over a 3-year period, especially given current interest rates. This is something that a firm would need to investigate further.
Things like quality of search, email integration and various features are things that have to be investigate on a firm by firm basis. A feature that one firm considers an essential deal-breaker could be irrelevant to another firm. Overall, my impression is that in terms of basic functionality, these programs are essentially a wash, but that specific firms will come to differing conclusions based on their needs. Firms that have specific detailed needs may find an advantage with one program over another.

Over the past several years I have written extensively about document management issues. The following list represents a kind of table of contents on the way to a more extensive document management white paper. The hyperlinks point to the source of that particular post or article.