I am obsessed with covered hoppers with etched grills!  I now have 10 (and growing!), mostly 2 compartment versions from Athearn. Most are ACF Center Flows (I once worked for ACF) with several straight side versions thrown in.

Using proto photos, I have been weathering this week.  So far only one car has become a rust bucket - most are moderately weathered.  I still have 3 to do and they are fallen flag roads so it is likely they will have some fade and embrace rust more fully - unless I patch them.