I read only the first page and I'm with Accum on this one. While I only briefly, and I mean BRIEFLY (5 minutes tops) tried the cyclo, I have used the Makita (still use), PC (still use xp), Meg's v1 & 2 orbitals, UDM, and Griots, along with the Flex. After working for about 1 year with a PC and 3+ years with Makita/PC (used PC for some Porsche, Nissan, etc. paint that were just full of hate for the Makita when it came to finishing) I can proudly say that I have switched almost 100% to working with ONLY the Flex. It corrects great with LC Orange and Meguiar's #105 and finishes down great, leaving me no worry of buffer trails/rotary holograms. Yes I got fairly good with the Makita and could finish down perfectly with it on almost everything, aside from a few black Porsches, Nissans/Infinity cars, but now I mainly use it for heavy correction when doing a 3+ step polishing. Anything 2 or less steps is generally M105/Orange or White followed by M205/white or black. It might take me 30 minutes longer (for which I don't charge) than the Makita would, but the fact that I know I don't have holograms (yes I still check every time) is enough for me to use it over the Makita for finishing.
Long story short, I think Flex is well worth the price and the hype it gets, because it really can correct great with the right pad/polish combos, but also finish out perfectly well with a finishing pad/polish. I use 5.5" pads 100% of the time on the Flex and they fit just fine on the backing plate. I do wish someone would already make a smaller plate, but for me it works just fine, as I can use the PC for smaller spots with 3" pads.
If I had to choose one machine, I'd easily choose the Flex.