looking for suggestions which is better a chrome molly barrel or chrome lined ??

In an AR, chrome lined without a doubt.

All AR barrels are made from chrome mooly steel unless they are made of stainless steel.

Any of them can be chrome lined ( it's a plasma application, not a plated one like your truck bumpers). Stainless steel is heavier than chrome moly. And they can machine is just a tad better than they can chrome moly. So, they can keep the barrel like .0002" ( that's 2 ten-thousands of an inch) straighter than an average c/m blaster barrel.

Now for the trick, most manufactures use a chrome moly steel of an alloy called 4140. That means that the steel contains certain elements in a precise ammount. 4140 is a great steel for rifles. My Remington sniper gun has a 4140 tube on it. But in an Ar, things change. If you have an M-16, a 4140 barrel will go tango/uniform very quickly on rapid fire. You need a different steel. ENTER 4150! This is the stuff they make real machind guns out of. It can take the heat that would ruin 4140. All M-60's the 240 SAWs and the old Ma Duce the 50 cal machine guns are made from 4150.

The only manufacturer using 4150 for all their barrels except for their stainless and National Match barrels is Bushmaster. Not even Colt used 4150 on their civilian Ar's .If it wasn't burst /full auto capable (there got 4150 barrels). you got 4140 steel.

BOTH SHOULD BE BANNED!