Yes, it's been very different from the NHS. I didn't expect to have immune issues (I don't have any symptoms, asthma/etc), and we went to ARGC mainly because of their v intense monitoring (and success rates!). They don't leave anything to chance - I should say that I think a lot of people think they go overboard. But I found it reassuring. They were monitoring my hormone levels and adjusting my drugs almost every day up till transfer, so they got the optimum moment, and in the 2WW they monitored my progesterone levels every other day and adjusted my dosage as my levels started dropping at one point.
The transfer itself was VERY different from the NHS one, which wasn't a bad one - but this one took 45 minutes / an hour because the doctor wouldn't start it until everything was lined up perfectly (I have a wonky womb so had to drink a lot to get it lined up; the NHS guy just shoved the catheter harder. OUCH. I also bled that time, which isn't good for the embryos.). We definitely left after the transfer feeling that that alone - all the care they'd taken with it - had made the decision to walk away from our funded NHS FETs the right one.
The other major difference with ARGC is the immunes stuff - they'll test everything under the sun and medicate accordingly. I didn't start my cycle till January 2017, having first gone to them in May 2016, because they had me on humira for ages trying to get my immune system to calm down. It didn't work, and I had a chemical, but I was reassured by our review meeting, where they went through that they thought might need changing for the next cycle (different immune drugs, different steroids, different oestrogen dosage, possibly).
Like you two, I have three embryos left - some days it feels like three will surely be enough (we started with 6!), other days it feels perilously as though 3 surely won't. It's no fun, is it. Best of luck @summerloving17 and @blondiecub0109, I'll keep everything crossed for you.