Just looking for some quick AV amp advice. I'm currently torn between the Yamaha DS-PAX630 and the Marantz SR5300. My problem is that I don't fully understand the growing number of sound formats out there, and I just want to be sure the amp I buy covers the majority of the new ones. For example, is DTS-ES the same as DTS-ES Discrete 6.1? I'd be very grateful if someone could give me a quick nod as to whether the DS-PAX630 covers these formats, or whether I should plump for the Marantz. Also, is a standard Dolby Digital/DTS-capable DVD player (Toshiba SD3109) capable of playing all these new formats? Does the amp do all the decoding? I'm struggling somewhat with this, to be honest! Thanks in advance.