An update:
After weighing options, reading guidebooks and frankly lots of procrastination, I decided in the last few days to spend my 4 nights in Brasov and found a good single rate at the Hotel Ambient, 65 EUR/night. The Sigishoara visit might still happen but this trip I think I'll try to concentrate on Brasov and area and Sinaia. Anyone with reviews of the Hotel Ambient I'd be curoius to hear, otherwise thanks all for the feedback. I'm looking forward to my first trip to Eastern Europe, an area I've been wanting to see for some time.