planning for voice over ip /ip telephoney for 150 users

I am planning for ip telephoney/contact center for my company from scratch,for 150 users ,I got qoutes from Cisco, avaya and 3com,Alcatal,.
here is the quotes,
please advise?
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i_harfoushAuthor Commented:
in 3 sites  named "Shuwaikh","Rai & Ahmadi Branches
Best advice is to get the names of business that these companies have done implementations for in your area, same scope, and go talk to them. See what worked, what didn't, what surprises there were, etc. Go to the customers rather than getting opinions.

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i_harfoushAuthor Commented:
can you please check the technologies they are using , do you have any comments about the switchs ,routers,call center .., in the qoute? I already met these people.
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Have you checked out ShoreTel as a possible contender? We implement that phone system for a couple of our clients and they love it. Also have another customer replacing their Cisco system for it. Worth looking at.
i_harfoushAuthor Commented:
I asked for this system , there is no dealer here in our country, mainly we are going for cisco
i_harfoushAuthor Commented:
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IP Telephony

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