The reason I'm asking about the 704 is because it's cheaper and fulfilled by Amazon so it gets free shipping. It also doesn't have an unneeded router built into it that I just have to disable. I have a gift card on my Amazon account that I was going to use for it. Right now I'm using a Linksys RT31P through Freeswitch via VOIP.MS, which doesn't support rotary directly (amazingly my bluetooth gateway for my cell phone does and so does the Arris modem for Charter).
I'd rather stay away from the pulse converters due to cost if there is another alternative. I was just hoping someone had tried this, since that's how the 504 was discovered to support pulse.