Telecom hardware or desktop solutions have gone through unprecedented change in the last few years.  Once an industry with only a handful of legacy PBXs (Nortel, Avaya, NEC, Mitel, Toshiba), telecom has seen an introduction of suppliers from the data industry, soft-switch manufactures, and open source providers.  The telephony delivery model compounds this change with hosted PBXs, collaboration with IT networks  self-made solutions, and SIP trunking.

So why do local vendors usually quote on a single solution?  And why are they only promoting analog lines or expensive PRIs instead of SIP?  Most local vendors do not have the expertise on staff and only a few customers are willing to pay for this expertise.  They are also in a situation where the vendors have signed agreements to represent only one or two manufactures to the customer.  This limits your options.

So if you are looking for a phone system that is very similar to what you have, just the new version, then this purchasing model may be the one for you.  The biggest advantage of this model is, for a price, you should have access to great post-sale support.

Good Luck with the purchase.