Going for FCs on high combo maps is a good exercise. When you've gotten more comfortable with holding combos in the 1000-1500 range all the Harumachi Clovers and ~300 combo maps out there will be easier to overcome mentally.
Trying is the important part so don't get discouraged if you still end up dropping combo anyways.
Trying is the important part so don't get discouraged if you still end up dropping combo anyways.