I had it done in Hyde Park also (at Max & Co) and my hair looked beautiful and full and lush, like a Playboy Playmate's hair!! It was sexy and flowing and had a lot of body. The only thing is that, I can't imagine getting it done that way often. It did seem harsh...but what do I know. I'm used to a stylist who uses a pressing comb that's WAY too hot.
Basically, the Egyptian technique (the way I experienced it) is like a factory. One person washes you, another blows your hair dry as straight as possible (which is where I felt the potential damage) and then another will flat iron you.
The blow dryer is a super hot one, that could get your hair straight on its own with the right technique. Its the Pibbs Twin Turbo...I think he used the 2400 or the 2600. I've known other stylists who use dryer and the thing is amazing!!
Anyway, I loved the way my hair looked. It held up very well! I just think with the Pibbs dryer - and they can be a little rough with your hair, pulling and tugging with the brush...I think it could be a bit damaging.
(Sorry for the long post!)