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Mizuno golf-ball searches can mix older RB Tour models with RB566 and the newer Mizuno Pro S and Pro X names. Compare the exact edition and regional specification before deciding. The useful first split is between the documented two-piece ionomer RB566 route and the three-piece Pro models, followed by the flight and feel you want to assess. An S or X suffix is a fitting distinction, not a quality ranking.
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Guide checked: 9 September 2026. This guide compares the linked published information. We have not carried out hands-on product testing. Model details and service features refer to the sources identified below.
| Option | Published distinction | Buyer decision |
|---|---|---|
| RB566 | Two-piece ionomer construction in the checked regional specification | Compare an accessible everyday ball with your current choice |
| Mizuno Pro S | Three-piece; positioned for softer feel and a mid flight | Assess pitches and normal approaches |
| Mizuno Pro X | Three-piece; positioned for a higher flight than Pro S | Check whether extra height is useful on your course |
| Earlier RB Tour / Tour X | Older names still appear in searches and offers | Use the matching generation’s specification |
Table of Contents
Separate the name on the box from the search result
Mizuno’s official comparison page includes Pro S, Pro X and regional RB products. The RB566 page supplies a separate construction description. Reading both prevents an easy buying mistake: treating every RB-labelled ball as the same product, or assuming an old RB Tour review describes a new Pro model.
Take a screenshot of the exact listing and compare its model name, colour and pack quantity with the box photograph. Regional names can differ, and a retailer may carry previous stock after a manufacturer’s main page changes. There is no need to reject older stock solely because the packaging is different, but its specifications should remain attached to that edition.
RB566: identify the construction before the claims
The checked RB566 information identifies a two-piece ball with an ionomer cover and a butadiene core. Mizuno also describes its micro-dimple design and intended flight behaviour. The physical construction is useful evidence; promises about your own distance require a trial. A higher dimple count is not by itself a ranking of aerodynamic quality.
Consider RB566 if you want to compare that construction with your current everyday ball. Pay attention to pitches that land short of the flag and release, and to the feel of longer putts. If the ball behaves differently from the urethane model you normally use, that is a reason to adapt the comparison rather than assume the softer-sounding name should have produced identical stopping response.
Pro S and Pro X: compare the flight you can use
Mizuno’s current Japanese comparison identifies both Pro S and Pro X as three-piece balls. It positions Pro S with softer feel and a mid trajectory, and Pro X with a mid-to-high trajectory. These are relative manufacturer descriptions. They support trying the two models for different preferences without claiming that either will produce a particular launch angle for every golfer.
Think about the approaches you face most often. On a firm green, useful height and landing behaviour can matter; into wind, a flight that you can judge confidently is also valuable. Do not buy solely by a preference for a low or high label. Compare the actual carry you need, the way the ball lands and the short shots that follow when a green is missed.
Use regional evidence carefully
The source comparison is a Japanese range page, while the RB566 source is Australian. They establish the named specifications, not a promise that every model and colour is currently stocked in Britain. For a UK purchase, confirm the product code and generation with the seller. Avoid carrying over regional prices, delivery offers or warranty assumptions.
An online image can show a different season’s box from the stock description. If the exact edition matters to your comparison, resolve that before buying several dozen. Keep white, yellow and other variants identified, but do not assume that colour alone explains a different result unless the construction is also confirmed to match.
Make a controlled change
Use the same clubs and a familiar practice area when moving between models. Compare clean balls with no obvious cuts, and note the response over several ordinary strikes rather than selecting the best shot from each. If you are changing both irons and ball, test one change at a time where possible; otherwise it becomes difficult to identify what improved the result.
Choose the model you can obtain consistently after the trial. A small saving on an unidentified mixed lot is less useful when it combines several Mizuno generations and makes every round a different comparison. Record the complete name and your own observations, then buy the same version when you replenish the bag.
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