Using SG300 directly as a router?

Question

Hello, I am building a new home with several Cat6 ethernet ports wired throughout (at least one to each room) and I want to connect them all through a rock-solid reliable gigabit switch like the SG300 or SG200.  I am also going to use wireless N (something like the E4200) but I would prefer not to use the wireless device as the router since I want a solid, reliable connection from my ethernet-connected devices and the Internet and I honestly don't trust consumer-level devices like the E4200 to be reliable without dropping my connection.  I have computers that need a constant VPN connection and I have other computers that do bittor...umm, network intensive activity that usually bring wireless routers to their knees  
So what I would really like is to connect the internet cable modem (Ubee) directly to the business-class switch (SG300 or SG200), and have that business-class switch do the routing and NAT to my entire network, and I'd just use the E4200 as a wireless access point.  I'm not a network admin and the idea of the CLI scares me, but I can probably use it to at least switch the SG300 to Layer 3 mode...that looks simple enough.  I'd definitely want to use a web GUI for everything else.  From what I've read, the SG200 is a Layer 2 device so it couldn't be used as a router, but can the SG300 in Layer 3 be used as a router connected directly to the cable modem?  Will it support NAT and UPnP and all of the other features that the E4200 would (minus the wireless of course)?  For example one thing I will want is to be able to have multiple XBoxes connected to the switch all with an "Open NAT".
If the SG300 can't do this, what's the best rock-solid business class device that I can connect directly to the cable modem that will support things like UPnP and NAT?
Thanks everyone in advance for their advice!

Answer 1

Hi Alan,
Interesting comment "'ll probably be moderated for this"
When this community was setup years ago, I recall that the moderators for this segments said they wouldn't censor.
There were a few exceptions, unless you were rude and used foul language or were obviously demented.
So you can have your say.
Plenty of contributors , probably including myself may be moving towards demented in our thoughts. But until we all get really loony Alan,  your free to say what you want. II's all healthy discussion.
I have seen many "interesting' posts but I suspect  your post will remain for years to come.  Once on the Internet, our comments and discussions are  left to embarrass us for years to come.
regards Dave.