I think it's easiest to split it by things like location (no. offices, office strengths), practice areas (check Chambers for Tier 1 rankings in each area the firm is top ranked in), and then maybe initiatives (if they're involved heavily in legal-tech etc). I've always answered breaking it down into these sections as I think it makes it clearer in what respects the other firms are considered competitors rather than naming the firms firstHow do you identify a firm's competitors?