I've talked a fair amount about Web-based vs. client-server student information systems. Both have their advantages and disadvantages, but as regular readers know, we made the move to the Web-based X2 Aspen SIS about a year and a half ago, after a miserable experience with Chancery's (now Pearson School Systems') SMS (also Web-based). Prior to that, we'd had great luck with WinSchool and MacSchool, the client-server based predecessors to SMS.
As a quick note, for those of you less familiar with student information systems, client-server systems are generally hosted onsite and consist of at least a single application server. Special client software runs on individual user computers to allow them to access the server and the data it contains. While this tends to give users a very speedy, richly-featured interface with multiple windows, client-server SIS tend to be limited to Windows (and Mac if you're lucky) and are only accessible onsite. VPNs and Terminal Services can mitigate this limitation to some extent, but obviously require additional administration.
Image Gallery: I’ve created a gallery from the latest release of X2 Aspen.
Web-based SIS, on the other hand, are accessible anytime, anywhere, assuming that your hosting is set up to handle that (some districts still choose to only allow access from within their network due to bandwidth and security considerations). They generally consist of an application server and a web server, but can scale up to use multiple web servers for load balancing, dedicated reporting servers, database servers, etc. As with any website, they tend to require a bit more clicking back and forth than a client-server system which can allow multiple windows to interface with a server at the same time. However, as AJAX and other rich Internet application technologies mature, the gap in look and feel between the two types of systems shrinks.
We ultimately chose X2 Aspen because it did the best job of balancing web-based accessibility with speed and functionality more often associated with a client-server SIS (their extremely competitive price also helped the decision). X2's extensive use of AJAX (which has increased significantly with recent updates) makes many of their pages feel more like Google Docs than basic HTML forms. Although X2 supports districts that host the system internally, the best bang for your buck comes from letting the company host Aspen for you in their data center. They handle backups (including offsite), security certificates, physical security, etc., allowing district staff to focus on database administration instead of running web, database, and application servers.
The Web-based nature of Aspen, like other online student information systems, also facilitates X2's outstanding customer service. Any time users call in with a problem, X2 staff can log in and see precisely what users are seeing and can often resolve the problem on the spot.
So what kinds of problems have we had? Overall, not too many. The worst have related to data conversion, largely because the data that came out of SMS were such a disaster. Now, the majority of our support calls relate to how to complete uncommon tasks or tweaks we need for various reports. All of the reports are written in Java and XML, by the way, so are completely editable by users; however, for now, it's a lot faster to have X2 make the changes.
While the system is generally well-liked by teachers and staff, there are a few issues. One is noted in the gallery, but, essentially, there are places where you would expect to be able to use snapshots (pre-selected groups of students), but can't. This is largely a front office complaint since they often need to work with groups of students on field trips, in sports teams, clubs, etc.
The second relates to speed. As already noted, this is a trade-off with any web-based SIS. The folks who complain the most about lag were the ones who loved our old client-server systems and were accustomed to nearly instantaneous data access. This is not to say users spend a lot of time waiting after each click. However, when someone has to enter a lot transactions every day (those in charge of attendance, for example) that can't be completed through so-called "mass updates" (i.e., they must be handled individually), then any delay between click and response can grow tiresome. This is obviously something that must be considered internally; for us, the speed issue was far outweighed by accessibility, but the same may not be the case at your school.
For any of you considering a new SIS, here's a gallery from the latest release of X2 Aspen (they just rolled out Version 2.6 last week). It includes the features I like and use the most, as well as the few niggles I have with the Web-based system. The screenshots are all taken in Firefox on my MacBook, but the web pages all function without any issues across browsers and platforms, including Linux.