Hi Neil - you may consider our 360 product viewer and software. Free version is available if you want to check it out. Also please take a look at our blog as we have a new version coming out that is improved to work without Flash (ie ipads, iphones, etc) and has a new high-res zoom and new html hot-spots. Beta of this new release is also available on our blog.
BTW: in terms of changing product colors it's hard to find something better than Photoshop I'd think - it's hard to impossible to completely automate color changes and usually requires producing a clipping path first and clipping path is quite time consuming and often a full manual operation. Just ping me if you need to know how we do it, otherwise there's a bunch of youtube videos that show it step by step - here's one for example.