I've been using ST1 for about 8 months now and the UI really isn't that bad. There is no doubt that this first implementation is far from perfect, but I dont think I am any less efficient than with V20. Clearly if you have used the SE as long as PerBear you will have gotten very proficient with a customized UI, so a major change will inevitably bring some loss in productivity. My guess is that the more flexible customization in ST2 will at least bring it on a par with the old UI.
Actually, I find there are some benefits. The task bar can autohide freeing up screen space.
The UI improvements in ST2 look to deal with many of the other annoyances. But as I said, it takes a fair bit of getting used to because it is quite different, though once you get familair with the layout it is OK.
I have also started to integrate Sync modelling into my workflow. It really was NOT love at first sight and my normal workflows just did not work. It was actually very frustrating. I have perserved though and found that a good understanding of Live Rules and how to manipulate them is essential to getting the desired outcome.
Even though Sync modelling is still a bit "warty" and lacks some functionality, I find that I am now reluctant to use Trad if I can help it. Fundamentally, there is a freedom in Sync that Trad just doesn't give you. I am not even saying it is quicker, I just like it better. It has really grown on me.
Personally, the more I understand it I thinks Siemens have really got something in Sync, but I think the "ease of use" thing is over-sold. It acutally has alot of depth and functionality that is not immediately apparent and needs to be well understood. If you just dip into it you will get frustrated very quickly.
With regard to copying Spaceclaim, I am pretty sure the development of Sync had started long before the release of Spaceclaim. Bear in mind, Spaceclaim launched March 2007 and ST1 in Aug. 2008 - hardly enough time to develop a whole new modeller. That said, the high profile of Spaceclaim seems to have paved the way for the acceptance of Sync. as the next progression of a parametric modeller.
Tony