I have used oral and injected methods, singly or in conjunction, for over 5 years now...
At the moment, my insurance does not cover injectable E, so I have been on oral only, and yes, I use it sublingually. I have no data to back up my assertions, but I am quite sure that dissolving the pills under my tongue or between cheek and gums gives me a higher E level than merely swallowing them. I have had two different prescribers, and both agreed with my observations. I have no doubt that micronized formulations would be more effective, but I haven't ever been able to get them, except for my progesterone, which is also bio-identical, and is now administered via compounded vaginal suppository. I looove the additional benefits of being able to break the suppositories up into pieces that reflect the dosages I need day by day, and the positive effect the essential fatty-acid base has on my vaginal tissues.
I prefer injected estrogen over pills. I like being able inject and forgetta 'bout it, and I also like being able to carefully adjust my dosages to coincide with my cyclic needs. I have also used injections and oral in tandem, with even better results psychologically, and, in my opinion, developmentally. My last endo was a huge fan of this approach for me, but I am xx intersex, so I am uncertain if there would be any advantage for someone born male and in an MTF transition.
My current endo/gyno say he has MTF patients that seem to also cycle to some degree, and he accommodates their needs accordingly. There is far more to cycling than just ovulation and menstration, and my body will attest to that fact, even though my uterus was mostly removed at a year and a half. I have leg and back and pelvic pain, and I retain water, and more. The day after my cycle ends, even if I am on a steady HRT regimen, I feel a great relief, and my pains subside. My emotional state also reflected my cycle even before HRT, and I can still be surprised by the bottom falling out of my emotional world 5-6 days before my cycle ends, or by a strong desire to copulate leading up to my 'ovulation' day. My cycle is synchronized to the lunar cycle, and though I can anticipate it, I pay it no mind, lol, but I always go through the same things, month after month, lol. I like it. It makes me feel more whole than I otherwise would..
Probably more info than you need, but hey, it's what happens to me...
Missy