50-50, depends on...

My gf is EE, ASIC designer for telecom, went back Sept and still waiting now.If you have to go back to get the visa, my suggestions is: avoid Guangzhou consulate, seems more major delayed cases on H1B are from there...Being in advanced engineering and previous visa was issured more than a year ago, you are more likely to be checked at any cosulate in china, the waiting ranges from 3 weeks to months, we went though 2 months of calling and waiting from guangzhou & washiontonDC, it really sucks, really.

I would recommand you go for 3rd country visa, avoid china. Canada and mexico will basically elimiate the risk. In fact I am going to mexico tomorrow to get the H1B so I can go back see my gf ( I don't wanna get stucked like she did ), a lady just posted that 10 chinese in mexico today all got visa without any trouble.