I drove 50 from Sacramento to WV back in 1988, so my memory is a little rusty and the road's probably changed a bit. I remember KS as being kind of crowded although 4-laned. MO being more of an old 2-lane. In WV, it is a highway as far as I-79, then a really curvy mountain road as you continue east, which was no fun at all on a dark rainy night.

I definitely consider these old roads worth the detour because they give you a chance to actually see the country, and stop places you ordinarily never would have considered stopping. My best memories after twenty years of driving these kinds of roads (I've done all of them from hwy 1 to 44 so far) are almost all of places I never really planned to visit. But they're definitely not for everybody, especially if you're just trying to get to your destination.

Driving these roads can take a bit longer than the Interstate, especially now that Interstate speeds are a lot higher than they used to be, but especially in the west and midwest, not that much slower. We usually budget about 250 miles/day (and we travel with 2 kids ages 5 & 8), so you could easily cover the trip to NY in 7-10 days. In CO & KS you'll probably cover a lot more than that each day. And of course if after a few days you decide the old road thing really isn't for you, you're never more than a few hours from a paralleling Interstate.

Thanks for all your input so helpful. Was wondering if you had the choice between US 40 vs US 50 which would you choose to detour on ?

I personally prefer roads that have little traffic, still go through towns rather than around them, are somewhat narrow and follow the contours of the surrounding landscape. As a result I'd probably choose US 40. Since most of it runs within a few miles of I-70, it sees little long distance traffic (since they're all on I-70), and is less likely to have been significantly updated (so still goes through town and hasn't been re-graded). It also has the big advantage that if you do find you want to avoid a busy area or make up some time, you're usually only a couple of miles away from I-70. On the other hand, it does have the down side (from my perspective anyway) that for much of Kansas and almost all of Missouri US 40 & I-70 share pavement so you'll be on the Interstate anyway.

Since US 50 is generally much farther from an Interstate, it's much more likely to carry people traveling medium distances (so may have a bit more traffic overall), and also as a result is more likely to have been improved by the various states, with re-grading, wider lanes, shoulders, and bypasses of towns.

BTW, if you'd like to know what US 40 looks like, I have pictures of it.
NJ - MO: http://travel.webshots.com/album/560441869iYgoME
KS - UT: http://travel.webshots.com/album/561048063RtpyTG

(The pictures are all westbound since that's the direction I traveled.) Sorry, no pictures of US 50, I drove that before I started taking pictures & haven't gotten around to driving it again yet.