If I had a good comprehensive and children that were switched on to education then I would probably opt to stay put.
Yes I opted to put my DSs into a Grammar school but that was because I wasn't confident that they would be self motivated enough to survive that particular Comprehensive. With hindsight my eldest would have been better placed in a well performing Comprehensive that provided extra support on the socio/emotional aspects. Unfortunately these are often harder to get places at than Grammars.
I would second that Tolstoy. I would have done the same for DD1 with hindsight. I have not seen much evidence that DD1 has achieved more at GS than she would have done elsewhere. As long as the comp is decent then there might be much to be gained from ease of logistics.