A huge debate raged when we were setting up a new phone system. The guys doing the install did not believe in paying high prices for Cisco gear when they could do the same things with lower priced alternatives. From what I have seen Cisco is rock solid and lower priced gear generally seems to burn out sooner.
How do you know when it's better to spend the money on Cisco equipment?
It's a simple trade-off of cost vs. risk. If you believe (or have anecdotal evidence or reviews) that Cisco gear would be rock solid, then it might be worth spending the extra money. Phone systems can be pretty central to a business' operation.
For some companies, saving (for example) $100,000 on a phone system is peanuts compared to the cost of 20 minutes of downtime if the phone system fails. On the other hand, for some companies, saving even a little money far outweigh the potential of minor problems occuring in the future. It's a cost-benefits analysis only you can do.
How do you know when it's better to spend the money on Cisco equipment?
Nobody ever got fired for buying Cisco...lol. That phrase has been thrown around plenty.
In my opinion, people go with Cisco because it is safe. You will always find people that can support it, just like MS stuff.
Funny thing about your OP though is that you state the "higher price" but Cisco sales guys, especially on a new PBX of theirs are more than happy to bring their pricing down to "get in the door" with you.
I personally shun away from Cisco, but that's simply because I prefer a sort of "best of breed" approach and believe Juniper (networking) and Alcatel (phones) have better products.
The Cisco is also more complex and requires more knowledgeable people to keep it up and running. I was involved in a Cisco VoIP deployment at one time. It worked well, had some minor issues with echo (as most VoIP does). There were a couple features we wanted that it didn't support yet (we did this very early on after they released the product), but we were living with it, knowing that eventually they'd add what we needed.
Unfortunately, we suffered a failure of the server (Cisco label, but essentially a re-badged HPaq with software pre-load. The group of us (myself having next to no Cisco experience, a couple CCNA/CCNP and a "almost a CCIE") never could get the thing to work right again. Parted it out, and bought a cheaper system that we could setup and maintain much easier.
The major problem with Cisco and other proprietary phone systems is that you have to be able to pay for support. If your company is in the habit of not paying on time and has frequent spending freezes, you might be in trouble if the system goes down and you're not current on your maintenance contract payments.
I've had pretty good success with trixbox and Polycom phones. If I wanted to add another phone, I didn't have to worry about buying another license from Cisco. You have to know what you are doing though. I built a box with a T1 card that hooked into an ADTRAN ATLAS 550 that routed the DID numbers on our PRI between our old phone system, the trixbox, and our fax server. This offered great flexibility with our setup and cost much less than going with a Cisco setup.
It's all about budget - and perceived 'corporate comfort'
We've been using Asterisk that we installed out-of-the-box from an ISO that 'just works' - and has been working for 3 years. We've installed it on a bottom-of-the-range HP server (but new and Xeon class) and use a combination of Cisco 7960/40 + Linksys SPA942 phones. All good, all works, all the time. I'd recommend it.
Oh yes, and we have a dedicated ADSL line and Cisco router JUST for the phone switch/HP server - which means we don't get any chop.
Mike
It depends on what you're doing, if it's complex routing there's four companies out there (for me) Cisco, Juniper, Foundry and Force10.
For switches the same companies, plus Extreme Networks and 3com.
For voice, if you've got the tech to do it, nothing comes close to Asterisk, and just go with whoever's phones are better for you, from Snom, Linksys, Cisco, Polycom, etc. (or a combination)
For wifi there's others.
(etc.)
Generally if you have good staff taking the step above the D-Link / netgear / linksys / whatever gear is worth it.
Also remember that most of the "top shelf" Cisco competitors are cheaper and often have a better product. Personally I find Juniper gear far better at the same pricepoint, but it's really aimed at the ISP market.
If you're a HP shop I know several fans of the HP switches, but also several haters.
