Fred is right. A year after Total Knee Replacement surgery most people's swelling is gone and the new knee functions well. However, as another poster mentioned, the first months are at least somewhat difficult. It starts with a hangover from the anesthesia, constipation, and difficulty sleeping. Probably the week after your surgery you will start physical therapy which has its painful moments as the therapist forces the knee to improve its range of motion. Somewhere between one and three months you will be able to engage in physical activities that were part of your life with your old knee - cycling, hiking, and, in my case, skiing. Doing these things one month out is relatively unusual; three months out is more typical. If you overdo anything during this period, you will not damage the new knee, you only create swelling and soreness in the soft tissues surrounding the knee.
Statistically, I believe that 90 or 95% of patients experience good outcomes. But some people populate the 10 and 5% whose outcomes are disappointing. Ask your surgeon about this. If, prior to surgery, you are not fit and/or you are overweight, these factors may work against you.
Finally, my surgeon used a customized prosthetic. You can read the description in the link below. These prosthetics are somewhat new and the surgeon using them should have some experience using them.
I am not a surgeon or medical professional, but I believe what I have stated is accurate. PM me for more info if you wish.
Good luck.
Tom
https://www.conformis.com/custom-made-knee-implants/