Mitel Aggregated Reviews

We’ve got about 300 Mitel phones in 10 different sites. They work great. I think in 20 years of using Mitel (from digital to now VoIP), the only ones we’ve had to replace are a couple that got physically damaged by something heavy in a warehouse.
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Mitel and the support from Frontier SUCKS ! The worst Voip System I have had to deal with .You will spend a month proving it is not on your side . Than After going through multiple different departments . It will suddenly work properly and they will claim they made no changes . Since August my company installed a Mitel system and it is less functional than a decade old cisco system . Less features than allworx. The system and the company are worthless !
My advice if it is in your budget dump it and switch to a new platform asap.
Shoretel was great before Mitel bought them I am not sure now
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Mitel has a dedicated T1 (via AT&T) for both offices for VoIP service. We run our data through Spectrum, but have it configured as a rollover in case the T1 goes down.
We checked into all the VLAN / firewall / IPS issues etc etc, hence our month of trouble shooting. My tech guys on both coasts have gone pretty deep with Mitel – at this point they just designed some packet monitoring code because they weren’t really sure what to tell us either.
Also our issues are the same for both coasts… but the offices were set up by different 3rd party Mitel licensed providers. The chances of 2 different companies creating the same random errors is very small. Which is why (to me at least) this is pointing to an issue with the service itself.
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I currently look after around 30 sites with roughly 2000 users. We use MITEL and it is a huge pain in the ass. They rely on a decades old operating system where the interface gets shinier and slower with each update. 3300s are a underpowered POS and forever make up new reasons to have SDS Errors which cripple the system if not fixed quickly. Each time you want a new feature you end up having to install another 2 new virtual machines to enable features that should be standard, and when one falls over it kills another site. That said, they are cheap, usually have great support and if you go with virtual appliance rather than their dogshit hardware you should have a better time.
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Mitel has gotten better but is clunky. Mainly use their cloud hosted platform.
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I won’t give you a review, but I will tell you that the cisco system will cost 5 times as much, be a pain in the ass to maintain and implement and will be sketchy in availability. At least in my experience. Mitel is superior in every way I can imagine, EXCEPT the voice quality for IP phones was not great in the past.
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