I am from Australia, but am currently living in Japan. I have my eyes on the Denon AVC-3570-N, or the Onkyo TX-SR800. These receivers are both 100 Volts, but Australia requires 240 Volts. Are there any transformers on the market, which are good enough to suit me - with 100% conversion performance? I hear most transformers would not be suitable with receivers, due to their complexity. I would like to know if anyone has done similar to what I wish to do, and if it is worth doing without any problems at all. I am talking zero problems.