There are many similarities, which is to be expected since the MX25 is an upgraded version of the MX23.
The steel in both irons is produced using Mizuno's Grain Flow Forging technology, which, according to the company, provides golfers with a soft, solid and consistent feel when striking the ball.
The MX23 and MX25 possess modified U-grooves, which affect ball spin rate, and a triple-cut sole design, which affects playability.
The MX23 and MX25 are finished with a double nickel chrome plating. They are available in every iron from 3-9 and a pitching wedge.
The MX23 is made with 1035 mild carbon steel; the MX25 is constructed with a 1025 mild carbon steel. That produces an MX25 club head that is about 10-percent softer, which means golfers have a larger margin of error with their swings.
Both the MX23 and the MX25 have a milled pocket cavity, but the MX25 incorporates High Energy Mass Impact Center of Gravity technology. According to Mizuno, this technology permits the greatest possible energy transfer from the club head to the ball.
Which is Better
Generally, an upgraded product is superior because the manufacturer has improved upon flaws, weaknesses or outdated technology. The MX25 is no exception because of its softer carbon steel and greater playability technology. Both sets of irons can improve a golfers game.