Recently, I replaced my OEM spring on my TX200 after 30,000 shots. I had TbT spring guides on it, and it really shot well with this combination, but the power had decreased from 15 fpe to 13 fpe. So I ordered a new spring from PA and new guides from TbT. At first my TX200 had an extremely harsh shot cycle after replacing the spring. Unfortunately, after shooting the TX for about 1,000 shots, the shot cycle was still extremely harsh. The rifle was real hard to cock, and when I shot the rifle, the sight picture jerked to the right. So I put the rifle in the gun cabinet, and just shot my AA S500 at this years field target competitions.Now that Winter has arrive in Wisconsin (11 F right now), my airgun club has moved indoors. We have what is call Indoor Field Target Practice (IFP), where we shoot 25 bulls , with a maximum score of 50 points. For this IFP competition, I shoot my TX200. So out came the TX, and I struggled to get 25 points last week.This week I was down in my new basement (I just moved) getting my gun smithing bench set up, and I thought: A few years back I tried out two Vortek tune kits: A 12 fpe kit and a SHO kit. I looked through my moving boxes, and I found the ziplock bag with the two Vortek tune kits inside. The springs were all lubed up with clear tar, so all I had to do was open up my TX and reinstall them. The first kit I installed was the 12 fpe kit, which had about 5,000 shots on it, and found that the power was down to 9.5 fpe. The shot cycle was excellent, with little recoil and no vibration. However, 9.5 fpe was just too slow for me, and the AA 7.9 pellets did not group that well.So out came the 12 fpe kit and in went the SHO kit. Wow!!! The TX now had 12.35 fpe, and the shot cycle was excellent. It's shooting AA Exact Expresses (7.9 gr) at about 840 fps. I took my SHO tuned TX200 to the airgun club yesterday, and after zeroing my scope, shot a 40 point IFP, after warming up the rifle with just 10 shots (see picture below). A 40 point IFP is considered exceptional IFP score for a spring piston rifle at our airgun club. During the shot cycle, there is no significant movement in the sight picture, and the rifle is easy to cock (about 22 pounds). The TX with the old SHO Vortek kit is more accurate than my TX was with my old OEM spring and TbT guides, and the shot cycle is much milder. So I am going to leave things alone for now, and hope that the old SHO spring does not break.I wish I took pictures during my retuning effort. One thing I notice was the SHO spring was exacting the same length as the 12 fpe spring, even though the SHO spring has two more coils that the 12 fpe spring. The amount of preload was just 1/2 inch for both springs. So the lesson I learned is to never throw away old springs and spring guides, unless, of course, they are broken.