Why do Harbeth P3ESRs sound different?

Hi all,  My audio friend has a pair of Harbeth P3ESRs in the rosewood finish. After I heard them I wanted a pair even though I have ProAc 1SCs and Tablette Reference 8 signatures and Spendor S3/5s. I went on Audiogon and found a pair in nice condition and a great price in cherry finish. When they were delivered I put them on the stands and played them. They sounded nothing like my other speakers, kind of dull. So I played them as much as I could for a month and they finally sounded better. After another month of playing I brought them over my friend's  place for comparison. His Harbeths sounded more open and with better bass. Not huge but there was a difference. I brought them home and played them every day for another month and brought them back over my friends. Same thing. My LR numbers are in the high 400s and his are in the high 1600s. He thinks it's the wood finishes like a guitar. I'm wondering if it's an improved production run like ProAcs claim they  can do with their products. Any thoughts? Thanks.