Jim,
Yeah have a good play, the designers are the best I have seen and a multi-column tree control, well blew me away when I saw it. The Demos are brilliant especially for the grid and the editors. You can even print the grid with layout directly from the component to the printer!
It's not just the grid that is it's strengh though (Although it is very powerful, multiple nested views, card, vertical, you name it). There is about 20+ editors that you can use standalone on a form or in the grid so consistancy is throughout. Skinning as mentioned is brilliant and you don't need XP themes to add a very stylish look and feel. Suite also comes with a skinning editor if you wanted to make your own.
Good reporting components too, barcodes and labels are a breeze and you can give your customers the reporting editor too, a must IMHO. Also good exporting facilities, inc. PDF.
Although I am singing it's praises I can only do so with having used Infragistics for a couple of years, the only thing I would say for them is that it has ASP.NET components as part of the suite but it generates way too much HTML compared to the standard DataGrid so I stick to that.
When DevExpress releases the Chart, Pivot and Schedule components it will be way to hard for anybody to beat them on the WinForms. Wonder if they could convert the functionality of the WinForms components into WebForm, hmmm that would seriously kick ass.
Geoff.