for the cost of these wifi routers and cards, it is far cheaper to get a standard cheap n300 router with giabit ethernet, then for the devices that need high speed, you can run some CAT6 cables to them and for the devices that just need internet access and basic LAN services which do not absolutely need 450mbit/s can use wireless.
I have used many high end N routers and you do not get the advertised speeds unless you live in a rural area, especially new ones where in order to comply with new rules, will downgrade your speed if theres channel overlap
Ps if you have a network where 300mbit wifi is not enough then 450 most likely wont be eough either as no wifi router on the market offers consistent speeds, theres always dips and spokes (even our insanely overpriced ruckus wireless access point)
If you are doing something like streaming uncompressed raw HD video across the network or something that requires a ton of bandwidth then gigabit ethernet is still the way to go
if you need good performance for a game console or network printer/scanner, then n300 is good,
If you use no lan services but use a ton of devices both old and new and only need the wifi for internet access, then 54mbit/s is good
When I was setting up a network for a local cafe, in order to improve compatibility, we used old wifi standards, (b/g and limited the rates to 2mbit/s so that a single user cant easily hod up the connection)
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