I have to switch back and forth between ack and grep all the time. Sometimes I use ack, sometimes I use grep. I wrote ack, but I've never stopped using grep, and ack has never been intended as a replacement for grep.

For most of the common ack flags, they are the same as grep. -i, -l, -v, -w, -A, -B, -C, etc. That was intentional, to minimize that whiplash.

One other suggestion is that you drop ack into your ~/bin directory that you sync between machines. It's a single Perl file, and that portability is a feature. As long as your machine has a Perl on it, you can use ack.