Use the kubota blades.
I have the same mower and have tried gator. They're a little thinner and they don't last as long. Went back to Kubota blades, as they are 100% designed for the baffles.
Trick to mulching performance is you can't wait 2 weeks between mowings, you ain't gonna cut 6" off the top. 1/3 rule. Cut 1/3 of the total length of the grass and no more. So if it's 6" tall, cut 2" off of the top. Second rule. Cut it DRY. Not damp, definitely not wet. Dry only. Third rule, overlap your passes a little. Fourth rule, SLOW DOWN. Rule #5, make sure the deck is LEVEL front to back and side to side. Lots of folks say it needs to be 1/4" low in front and that's somewhat true but it's a generality. As a general rule, it till take less power to cut if the deck is slightly pitched in the front, HOWEVER, cut quality almost always suffers a little. How? Biggest difference I saw was that with it pitched even 1/8", I'd get 3 vague stripes in the cut grass. At zero pitch I have a well-defined 48" wide stripe instead of 3 16" stripes. On that note, most people check the deck level incorrectly; and I'll leave it at that. Rule #6 keep the blades SHARP and replace them if the tips get rounded even just a little, and if you are mowing an area that has some sand or a lot of loose dirt, they're gonna wear fast which is another reason to use kubota blades since they are a little thicker. Rule #7 FULL THROTTLE only (not half not 3/4, it needs to be full throttle and honestly if you have a tachometer, set your fast idle speed to 3550-3650 no load/hot engine. Rule #8 keep the underside of the deck clean. Buildup reduces airflow and capacity to recirculate uncut clippings which seriously affects mulching performance.
I use mine to mulch leaves and pine straw in the fall/early winter and it turns both into powder which disappears the first rain. Pretty impressive.