If you are looking for a Quantum baitcaster, the first thing worth knowing is what the brand's own catalog currently contains, because it is not what most searches assume. Quantum's official store lists spinning reels and no casting reel at all, and our own specification set has no Quantum row in it either. That does not make the question pointless, but it does change the answer: this is not a page that compares Quantum baitcaster models, because there are none in the current catalog to compare. What follows is what the catalog actually shows, why this page is short, and what to check if you find a Quantum casting reel on the used market.
Quantum's own shop is built around spinning reels, and the current range reads as a complete saltwater-and-freshwater spinning lineup rather than a mixed catalog. The reels the brand publishes are the Strive, Benchmark, Merit, Cabo, Exceed, Adapt and the Merit Free Liner, all spinning reels, alongside spinning combos and a rod line. There is no casting reel among them, and no baitcast category in the shop navigation. Whatever Quantum baitcasters exist, they are not part of what the brand currently sells direct.
Two rules decide what goes on this page. The first is that series names have to be published on the brand's own site to appear here, and there is no Quantum baitcast series on the brand's own site to list. The second is that specification figures come from our own CC0 reel set, and that set has no Quantum row at all — not a casting reel and not a spinning one. With no current series to name and no captured spec to quote, the honest version of this page is short. The alternative — filling a table with model names from old listings and numbers from nowhere — would look fuller and be worth less.
Older Quantum casting reels do turn up secondhand, and if you are looking at one, the questions are the same as for any used reel. Check the brake type first, because a magnetic or dual-brake system is easier to set for a lure weight than a centrifugal-only one, and the reel's braking is what decides whether it backlashes on a hard cast. Check the drag stack and the spool tension knob for smoothness, since a used reel's drag is the part most likely to be worn. And check that parts are still available: a reel the maker no longer lists is one where a broken sideplate or a stripped gear has no factory answer. The reel parts page covers what each part does and which ones matter most on a used reel, and the cleaning page covers the service a secondhand reel usually needs before its first trip.
If what you actually want is a working casting reel at a low price, the brands that do publish a current casting lineup are the better place to look. KastKing and Lew's both publish their casting ranges, and the models by brand page covers the rest of the field.