Old Army saying, "opinions are like 'iceholes', everyone's got one." And no matter what anyone says, the wood of the bass makes a difference, the bass's acoustic tone will shine through.
I've used oem Fender, Lakland, Barts ( not in a J config), Nordy's and Aeros.
I liked the Nordy's but the AEROS out ballz them.( in different J basses, so its a suspect observation) As a 5 string player, the low Hz on the AEROS is to die for. MUCH better than all the other pups listed.
Stock OEM Laklands were pretty vintage sounding, kinda hollow if you know what I mean.
Check the J pup sticky mega thread by SMASH at he top of this forum. Read it ALL. Its what led me to AEROS and I couldn;t be happier. Hard rock, funk style. Alnico 5 magnets. Powerful little suckers.
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Your first move since its a cheap knock off, is to measure both pickups and see if they are a standard size.
I'm a sound nazi, so I would settle for anything but the best ( AERO), but, beleive Seymour Duncan Antiquities are 1/2 price of he AEROS. Might have enough left over for a preamp.
Which you wont need one with teh AEROs. If they sound isnt hot enough, move the pups closer to the strings. At about 4mm, its overkill, too HUGE in my j bass. ( which has a deep acoustic sound). Ballz the size of New Jersey.