AO, welcome. Yes, biwiring is of no benefit and the type of "biamping" that is sometimes suggested with a receiver doesn't add any more power. There's just one power supply section in the receiver and feeding a speaker through two sets of output transistors(one being previously unused)rather than one can't create more power; the output transistors just act as valves to measure out the required amount of power.
The new 605 would be a fine choice for a receiver. The best deal now appears to be at
J&R , but they're out of stock because of the large number of orders they got at that price. So, you might have to wait a month or more there if that's important to you. The best price reporting it in stock appears to be $460.
