My opinion is never fall in love with a stock...even if it is BRK or FFH. Love your portfolio and how you can compound it while sleeping at night.
What you own is less important than making sure you apply Buffett's margin of safety and use intrinsic value for your purposes to compound capital.
If I only owned BRK, then I would never have benefited each time from the huge discounts I bought other stocks at...including FFH, OSTK, M, Odyssey Re, META, GE, etc. I did better than BRK and the S&P500 by doing so since I started buying stocks in 1999.
Cheers!