Thank you for the welcome to the Forum here.
Is it best to do the DPMS system or not, I've no definitive answer one way or the other? I surfed the net 'bout 'em, and did order one. So in time shall be able to provide my 'nose' on it later (opinions are like noses: everyone's got one. That's a bit more polite than referring to the sour end of 28 ft of intestine, k'!). I've mostly used 1911's with minimal updgrades (a basic worked over one by Jim Hoag Gov't Series 70 is the most I've had done to one). Most other pistol brands (Glock, Radom, Ruger, Colt, Berretta, Browning) have been used pretty much in their factory issue mode.
Reading posts in the Forum here: 1. ordered a Wolf 16# spring; 2. a Steve Bieder full length guide rod - it arrived yesterday, VERY nice work he dose; 3. a DPM System setup. Yes, can't use a full length guide rod n' the DPMS at the same time.
Will find how it works n' share my 'nose' here in the Forum. It will be about a month before receive it, as am traveling soon and it will have to be forwarded to me. As for the spring that's in it now, no idea how old or tired it may be, so shall replace it with the 16# spring and go from there. By all means, as one reply mentioned: preventive maintenance, maintenance/clean/magazines and keeping a tab on springs is paramount for good reliable pistol performance.
Most all ammo to be used (at first anyway) will be factory spec 230 gr. FMJ, maybe some 185 Gr FMG also. Not out to hotrod this fine pistol. If want more umph from a pistol will drag out a 10mm with full loads (not trying to start a debate here either!!). Again, I've not had the opportunity to fire this 97 B yet, and it will be at least another week+ before can do so. Though I've hugged it several times since it came into my care...!