I just did the CBA buy-back calculator for my SMSF, with me retired and a certain CGT cost base. 16.4% gain with the buy-back Vs selling on-market now, assuming selling at $100 and a 12% buyback discount (although it doesn't include brokerage if selling on market, so the % buy-back uplift will be greater). 22% gain if its a $105 price.
Against this is the potential for capital appreciation after buy-back (should be some, although only ~6% of shares being taken out) and dividends for the next X years - I'd expect ~$4 pa. So on a NPV basis, it looks marginal - but what's the WACC?
I might tender some with a low % discount, so that its only a better return, if accepted.