I have been on estradiol injections for more than 2 years. I started with estradiol valerate and now use estradiol cypionate because my insurance changed and the new carrier does not cover valerate. I am over 40, so I was worried about clots, etc. with the pills, and taxing my liver, yada yada. So, I opted for the periodic injection (and I still run 5k 3-4 times a week, and my Primary insists I take a baby aspirin every day to avoid clots). To me it is easier, esp. if you have no problem with putting needles into you, and have a good aseptic technique. I can't stress the sterile technique enough. I have never had an injection get festered up or bother me. I also inject progesterone, too. If I could inject my spiro and aspirin, I would do that, too. ha! I hate taking pills...I forget sometimes.
And Ms. Grace it right, you do get your highs and lows with injections (my wife can attest to that..lol) but I have gotten used to them and they don't seem to bother me to any real degree.