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Meng-- I'm sure the OP did not mean to compare primary vs. jump reels, but rather sidewinder vs. lantern grip reels.
BTW, I seem to have no problem at all fouling both types of reels...... Further in the article, they also state that the spool should be machined as close to the frame as possible, to limit the likelihood of the line spilling off the spool and jamming the reel.
The top one works and is near impossible to jam. The bottom one is a DiveRite POS that jams just by looking at it and has bits that break (like the nylon lock screw) when you really, really don't want them to.
The top one is a well thought out and finely engineered piece of kit. The bottom one is a piece of crap that was probably designed with a crayola on a dirty diaper by a 2 year old.