Hi Ryan,
Yes, using a chip with two CCP modules will allow you to get the absolute best results.
Basically, what we're doing here is the same thing as the CCP module is doing when operating in capture mode except that we are polling the input pins in software in order to determine when to "capture" the timers value while that's being done all in hardware when using the CCP module.

Polling the inputs like in my example will always introduce some latency, jitter etc. You said your preferred hardware for this was the good old 628/648 (which only got one CCP module) so that's what I tried to do :-)

/Henrik.