We chose the grammar, an hour door to door via bus, over the local outstanding comprehensive a 5 min walk away. (It is a true comp as there are no grammars in our county). 95%+ of local kids go to the comp, only 1 or 2 every year from the primary go to the grammar.
I think they would have done well which ever they chose, so in the end I let them have the final decision. We looked around both schools and spoke to people who had kids at both. I felt my kids had to be involved in the decision as if they chose the grammar then they had to be happy with the extra time spent on the bus, not being with their friends etc.
At the grammar they are out of the house 7.30 - 5. Had they gone to the local school it would have been 8.20 -3 three days a week and 8.20 - 4 the other 2 days. So they lose over 10 hours a week at home due to the school they chose. But getting the bus and going to a different town has been great for their independence.
The grammar has a huge catchment so the student population is way more diverse in terms of race, religion, home languages etc which has been great for learning a bit more about the world compared to our very small world town.
My eldest has particularly found her own tribe at the grammar, it's given her the confidence to be the geek that she is, which I'm not sure would have been so easy at the comp. There are far more like minded souls.
I'd also say the facilities in terms of sports, music, science etc are far better at the grammar and they offer more extra curricular activities than the comp but that could just be down to the individual schools rather than grammar Vs comp.
I would visit all schools you could realistically send your DC to (I think 1.5 hour commute is too far though, maybe just go for nearer ones) and really make the DC involved in the process as if they really want to go with their friends to the local comp, going through the whole 11+ process might be a waste of time. They need to want to put the work in to get to the grammar. You can't do it for them.