Pearson Fliers were Pearson''s answer to th J-30 but frankly the Pearson 30 got the question wrong. I have raced on Fliers a number of times and they are really hard boats to sail to their rating. While the J-30 has never been one of my favorites, the Flier has not proven to be their equal.
There were a number of boats designed in that era that are pretty much the equal of the J-30. I personally like Kirby 30''s and Shockwave 30''s although the build quality on the Schockwave is a step below the others.
Pearson Fliers can often be found for sale substantially less money than the J-30 if your plan is to go racing than I would stick with the J.