We're looking at a couple of options. First is keeping the current fiver, which will be more than enough for our needs, but the TV is not; we drove a new Mega yesterday, and the wife finally agrees the larger rear cab is needed, as my oldest will be about 6' by the time we hit the road (she is already squashed in the quad). We both have back problems, and need to be able to further recline the passenger seat, which is nearly impossible now. The cost is the issue, even used (found some 06 models near me, still asking over $35k
The real 'to you' cost is what you pay for it, what you sell it for and the maintenance etc. costs while owning it. Something a little more expensive is tying up more money but at the end of the day might cost the same or even a little less than something that was initially less expensive but cost more in maintenance and other owner costs.
As to the mega cab, the earlier models had a lower gross weight and therefore a lower payload. The more recent ones are more in line with the 3500 crew cab for gross weights and payload. Any of the three crew cabs from the domestic manufacturers are almost as large as the megacab. If the crew cabs are insufficient for your family an option is get a travel trailer and use a van or SUV; both are suitable for carrying larger families.
