Vandersteen 2wq with Mccormack dna .5

Fellow audiophiles,
If there are folks out there using A Vandy 2wq sub with Mccormack DNA 0.5 amp then then I would like to know what value of crossover is working for you. I have tried 100k, 75k and 50k fixed crossovers and it all sounds the same to me. I have the crossover box and played around with different settings but haven't quite felt that 'aha' moment. I have had this combination for over a decade and the system has been used in various homes in rooms of different sizes. It has sounded different in different settings but has consistenly left me wanting for more. Am trying to figure out if there's something that is truly wrong or whether I should stop wasting my time and live with the way it sounds. Any feedback is appreciated.