I would go along with that, in fact I would say for most people "want" is almost always the key factor in a buying decision - the only time need comes into the equation is when one is trying to justify that decision later! When "need" takes over the decision process you have what the sales bods call a "distress purchase" (i.e. thouse tyres will not get through the MOT).
Personally I installed a PBX because I wanted one - I am sure I could have coped without.
Having said that DECT never really entered into the equation - as would be the case for most people who already have a telecoms setup. Why throw out lots of good working handsets that are comfortable to use, just so you can have a dinky mobile sized handset that keeps getting lost, and runs out of battery half way though a call?
Wiring is a non issue - a PBX will not introduce any extra assuming you already have hard wired sockets in each room.
A PBX will:
Deal with Fax and modem traffic with ease Support multiple lines with ease A PBX will let me transfer a call to a (predictable) location rather than somewhere in the back of the couch! The speaker phone on my office handset works better than any I have found on a DECT setup, it has a headset attached with variable gain amplifier which is ideal for doing tech support when using computers. When my daughter gets older I can set selective call bars on her extension, and limit max outgoing call duration ;-) Incoming lines can ring appropriate handsets and get diverted to the appropriate answer machines.
So other than costing more and offering less what has DECT got to offer?