Thank you for your using GooCalSync.
GooCalSync has now performance challege. In my case of 815 entries in iCalUID view, it takes around 3 to 15 minutes to synchronize depending on Google site load degree.
I think that thers's room for improvemnt, that is, function to specify end date, optimization against reccuring event handling, reajusting fundamentally, and so on. I will go and do KAIZEN, please be patient…