I voted stock but maybe should of said it depends. Any kind of mag wheel just looks wrong to me on full size cars unless it was factory such as the two below for the Galaxie and Electra. Now on my Dodge it came with the stock covers but with the hard to find correct red centers. To be honest I find them incredibly boring so I looked for something else. I found it off of 1970 Polara I believe and feel they impart a little more sporty look than the original.
I have done the same thing with my 67 Park Lane. Two covers available and while the first one isn't bad the second one is more interesting. Both are best when the black hasn't faded. Plus 66 used no black accent while the 67's did. Took me years to locate the second set NOS to go along with the first set NOS to replace my original faded and dinged set.
You asked about 2 wheelcovers earlier and I saw no replies. The Chrysler wheelcover below was 71 only used on NY and T&Cs. The 67 Imperial is wearing 64 wheelcovers (1 year only ).