Yeah, awesome 45 for sure. I love mine. I kept my trigger stock. After 500 rounds it's pretty damned nice. Though I still might switch it to SAO just like you did.
The first thing I did was lose the goofy fiber optic front sight. I replaced it with a set of steel Meprolite's night sights from CZ Custom I believe it was, (easy swap.)
For a holster: Comp-tac "Minotaur" is the best and most comfortable I've used/tried. It really distributes the weight of the pistol evenly, especially with a good belt. Beltman "Bullhide" leather belt. That combo makes the big 97 hide really well when worn @ 4 O'clock.
For mags, Gregcotellc.com is going to be your best friend. The Mec-Gar magazines options he has, (Mec-Gar is the maker of the OEM CZ mags btw), they are solid and 40% less than the CZ mags... I ordered (6) from him before the election and they all function exactly like the ones that came with the pistol.
Lastly, the stock recoil spring CZ installs in the 97 is rather light, 13lbs to be exact. First range visit I noticed the 97B was, smooth accurate, and reliable. However, when shot back to back with my beloved 1911, with the same exact ammo... The 97 had more recoil; and it shouldn't since it weighs more than my 1911. After some research, I ordered a Wolff "Extra Power" recoil spring calibration kit that comes with 16, 18, 20, and 22lb recoil springs. The 18lb recoil spring made the 97B as smooth as butter and recoils a tad less than my Springer 1911, making faster back on target than my beloved 1911. Functionality was 100% with both the stock CZ recoil spring and also the extra power 18lb Wolff recoil spring. However, the 18lb Wolff spring made the 97B really shine though because it became much smoother and lighter recoiling than my 1911 to shoot. The Wolff spring kit was less than $30 delivered and well worth it. The SKU # is "13121" ...This is my experience with the 97B... Enjoy your pistol OP, it's one I'll keep forever! I'm linking the calibration spring kit for you below...
XP Calibration Kit