Can someone with experience implementing Visual WebGUI please share any cons of the technology. It offers a very intriguing model for implementing rich data-driven applications. I'm curious to hear any feedback that highlights limits or areas where it doesn't provide you with key capabilities.
This product seems to have gone under the radar, yet what it seems to provide is invaluable.
Visual WebGui used to be open-source. At that time I was checking it out to do rapid development; it struck me as "What Webforms Was Meant To Be." But at the time it seemed too fringe and too immature, and I had already been burned by webforms, so I went a different direction and started developing in ASP.NET MVC. The idea of developing something in Visual WebGui without having a good understanding of what was going on underneath the hood was just too uncomfortable for me.
I can understand why something like Visual WebGui would be very attractive to a Winforms developer (I myself was a longtime Winforms developer), but that's not the direction I went. Maybe if the Gizmox technology had been more mature at the time...
That said, I see that Gizmox has apparently gotten civilized; his website looks pretty nice, and it looks like he found some investment capital. I hope it works out for him. I really like his concept of emulating Winforms. That said, Winforms development itself is undergoing some evolution; some developers are now favoring a MVVM (Model-View-ViewModel) metaphor that provides better testability and other benefits.
There are some alternatives. ExtJs comes to mind, as does Telerik controls. If you eventually venture into ASP.NET MVC or Ruby on Rails there are a raft of jQuery plugins you can use in the browser, and usable client-side programming (via jQuery) is very cool.