I've had FIOS for 4 years and love it. I might be moving soon and one of the top priorities for buying a new house is that it has to have FIOS.
Yup I've had Fios from essentially when they turned it on in MA and overall its been a decent experience. Let me establish here are my general complaints with any cable company:
1st no option to purchase you box
2nd no real option to have a DVR that doesn't somehow add to your monthly bill
3rd although this isn't so extreme with fios but its still there, new customer promotions tend to be too aggressive and I find it insulting that I constantly need to cancel and resign up to get the best promotions.
1 and 2 are kind of true, but not exactly. While you can't purchase your own Verizon box there is the option for cablecard tuners. Either tuners that work through an HTPC like the Ceton InfiniTV or HD Homerun Prime or standalones like the Tivo and Moxi units are available. I use an InfiniTV4 in an HTPC and prefer it because there is no monthly fee for guide listings like there is with Tivo. With the above you only pay for cablecard rental from Verizon with, iirc, is $3.99/month.
While there are some drawbacks to using cablecard tuners (no On Demand or PPV) the additional capabilities like using extenders to other TVs in the house and being able to stream movies and music from a server outweigh the drawbacks. Also, for On Demand you can always use Amazon, Vudu, Hulu, HBO Go, EpixHD, etc. and for PPV you just have to make a phone call and then tune in the proper channel.