I am approximately 50% of the way through The Lonely League with a game clock of ~10 hours. I feel I've played more than enough to state that this is worthy of your time, particulary if you enjoy the source material the game is based off of.
I don't normally play Tactics RPG's - I've never found one where the story has gripped me enough to endure the lengthly battles that accompany the genre. This is not the case with LL -- the story continues to intrigue, and that for me is one of Calunio's biggest strengths.
Regarding the battles themselves... On occasion, I'm uncertain as to whether my success is based on pure luck, or good strategy. A fine balance of these two things is often challenging to hit, and not all players will be happy with Calunio's approach - since it can ramp up the difficulty somewhat. However, if you persist and search for new and alternative ways to tackle each situation - you'll bank the rewards.
FInally, the game is a visual delight with a lot of care and attention to detail that follows and builds from Calunio's previous works (THERAPIST: Mind Manager) - I appreciate this a lot. I cannot stress enough the charm that has gone into The Lonely League. I adore the cut-scenes (that sometimes have these neat little interactive parts) and the emotional beats between scenes. It's an all-round great package.
Oh yeah, fantastic music selection too.