Erm .. so if it was so good, I point you back to your question. Where is it now? I don't get this flakey IDE argument (MS). I see a lot of people make this sweeping argument about the IDE being flakey. From 'my personal experience' I don't have issues with VS. I find it reliable, and I'm productive with it. Sure there are things I wish worked differently and in some cases a couple of hours with the Macro IDE and I can do that myself. But I just don't get the flakey bit. Maybe I've not come across the issues you have had. As for a competitor to MS, the dev market is huge and a decent effort that attracted even a small percentage of that market (ie sub 1%) would be a going concern. I'm a great believer in competition and survival of the fittest, it just might be that the fittest is surviving.
The only thing unpredictable about me is just how predictable I'm going to be.