Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
The feature navigator tool (support contract requirement?) might be used, but you normally start with your requirements and then see if they are met.
PS:
An example is what Martin mentions, i.e. routers generally offer NAT and "small" L3 switches, like your 3750X do not. What we don't know is whether you'll need NAT, although there's a good chance you will if want your LAN users to have Internet access and if you don't have any other appliances.
Another example might be site-to-site VPN, again you'll find this feature on most routers but not on most "small" L3 switches.
