I was a Formula Fan
They look cool, got all the right top reviews...
I've owned Oro's, One's, Bianco's, Mega's
Almost all of them suffered a whole heap of issues. I sent some back for warranty replacement, others I had to get bigger rotors (200/180) to feel as if they were capable of hauling me up
And, yes, the squeel - oh my lord the howl. The rest of the group were always on at me, walkers would get scared to death...
I tried ALL MANNER of stuff to get rid of it - sanding, isoprol alcohol, pads, eamiling Formula loads of times (a chap in the US was very friendly), strasightening out discs, different wheels, torquing spokes, changing the forks, changing the frame, losing weight... all failed
In the end I went Shimano and have been a very happy braker since
The XT's on my current ride are completely faultless
A mate brought SLX's and has been very happy too
Zero squeal, loads of performance. Quality
Give your Formula's away, buy XT - it will pay you dividends in short time