When I went nearly three years ago for DS (no Harmony then) they gave me a 1 in 34. But they were brilliant, and I didn't feel it was impersonal at all. They answered all my questions, no matter how bizarre or technical. I even got to meet the professor who was every bit as eccentric as I'd been promised.. encouraging me to throw tissues across the room and hit the bins and so on! But very reassuring when it came to important matters too. He said he was sure my baby did not have T21 from the scan despite the high odds but obviously only an amnio would tell us for sure.
I chose to wait it out as even in the hands of the FMC, I knew I couldn't live with myself if anything happened and we wouldn't terminate for T21. Longest wait of my life, but as the professor thought, he has typical chromosomes. I actually got a "late" amnio done at 32 weeks which gives the same risk of preterm labour as of a loss earlier on, so it is pretty much safe at that stage. I didn't want delivery day overshadowed by studying DS's eyes, palms etc.
I was so pleased with the service I went back for the anatomy scan as well - far more in depth than the NHS one.
I posted a lot about my experiences at the time on this board, but under a different name! Had to namechange after MIL found out my name on here.. it began with "spark" in case anyone is wondering, and ended in "lies" 
Nearly 8 weeks again now, and I am so, so, so relieved Harmony is available this time round after the stress of the last pregnancy. I would not wish that wait on my worst enemy. I'm scraping in with literally a day to spare for the special offer and will be down there in a few weeks. Hurray for maca powder causing me to ovulate a few days earlier than normal this cycle, saved us £400 
Hopefully the service will be as good as last time, I guess I'll find out soon!