I do agree with Kyle ..maybe i should of elaborated my concern would be that you would have a unsupported solution by any one vendor that would take a lot of time to plan , configure, test, troubleshoot , when all that is taken into consideration the saving on capital outlay could soon become irrelevant.
It is the amount of devices that concerns , but that said you need to make an informed decision and i would get any prospective vendor to prove the solution works to you in a clear and concise way.
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