The main reason I chose 1934 and up is that it is the 'second half' of the wheat cents, the last 25 years. The first 25 years would be brutal in MS-66 RD, except for pieces like the 1909 VDB or 1930. I just swapped out the 66 1943-D for the 67 I had. The 66 has more luster, but the 67 is semi-prooflike and pretty sharp too.