Thought I'd describe my experience in getting UFB service since it wasn't plain sailing and it contains a couple of warnings.
Being in one of the first UFB-deployed areas (Whitby, Porirua) I decided to take the service as soon as possible. The first ISP out of the blocks to drop flyers in the mailbox was Orcon - a call to my existing ISP (Slingshot) was unfruitful. ("UFB? Oh yeah, hang on, let me ask so-and-so...")
So I applied with Orcon which wasn't straightforward - the "register interest" pingback on the website wasn't working, and the first person I spoke to on the phone in response to the flyer was unaware of it.
Anyway, I ordered the service only to be told that while the fibre was laid, it wasn't available for connection yet. They were waiting on Chorus.
They took my details and we set up the direct debit and chose a plan etc, then it was a game of "hurry up and wait" - they said they'd contact me a few days before the install was due, and that it would be contractors doing the install so they'd send the Genius router ahead of the install.
No such notification ever came, I contacted them at approximately monthly intervals. Then one day when I was fortunately working from home, the contractors turned up unannounced to install it. Orcon hadn't sent the Genius Router, nor did the contractor have one (they were contractors to Chorus, not Orcon).
So - the fibre was installed. This was uneventful - they consulted me about where I wanted the ONT (Optical Network Terminator) and went ahead and installed it. Badly. Holes in ceilings not matching the location of the capping, capping bent so accommodate ceiling skirting board, you name it. Suffice to say the craftsmanship was very low on the Wife Acceptance Factor :D
After they left, I contacted Orcon who were as surprised as me that the install had been done. They'[d had no notification from Chorus. They then couriered the Genius modem and I went through the process of setting it up with them on the phone which was relatively painless.
I've found the speeds to be as advertised when using speedtest.net to NZ based servers. I didn't open the taps fully so am on the 30 down/10 up plan. That seems sufficient for our needs at home. I was more interested in UFB for the reliability and future proofing than raw speed anyway.
I've found the Orcon Genius to be largely stable although sometimes it does crash and need restarting. Beware though, it has only three effective ethernet ports. The wireless is N300, 2.4 GHz only. It has a good long reach, no blank spots through the house or deck.
There have been a few outages, but I would say it is more reliable than the ADSL2+ connection I had previously. Speed seems consistent.
The VOIP service works well. I plugged my own handset into the router.
My biggest concern, other than the horrible installation job, is that the ONT has a very proprietary-looking power supply, which looks like an OEM part. In the event of a failure I predict having to call Orcon and do the Orcon -> Chorus dance to get a replacement. It's certainly not a generic part that could be replaced by a panicked Sunday afternoon trip to Dick Smith's or Jaycar!
So to my recommendations:
1) Stay in touch with your ISP throughout the process. The communications between the ISPs and Chorus (and its contractors) is not great.
2) If at all possible cable your place with Cat5 before installation, so the ONT can be installed somewhere inconspicuous and you don't have to have the builder's apprentice putting lots of holes everywhere for the optical fibre
3) if it's at all possible, as an insurance against failure, see if you can get them to supply you with a spare power supply for the ONT.
Finally - I don't know about the other ISPs but Orcon use VLAN tagging for traffic prioritization, and the majority of domestic-grade routers don't do VLAN tagging on the WAN side. So if you want to use your own router on the ONT you're out of luck. Also - familiarise yourself with the difference between Committed Information Rate (CIR) and Excess Information Rate (EIR) - the committed speed is "only" 2.5 MBPS in both directions, although I have no problems hitting the 30/10 I'm paying for.
Sorry this is so long...