I presume you mean buyig the new AirPort Extereme. There is no advantage to you if you already have N capabilities on your current wireless base.
Wifi standard changes always have a chicken-and-egg problem. You don't want to buy a new router if nothing you own uses a standard, and you don't really care about the standard being present on something you're buying if your router doesn't support it. It's up to you where to draw the line. Personally, I've found that over the course of 2-3 years after a standard launches, I've come to own enough stuff by happenstance that it becomes worth it to get the upgraded router. Or, my old router just dies and the price for the new standard has dropped a little so I may as well get it for "future proofing".
Generally speaking, most people's internet connection isn't limited by their wireless router. E.g. my Wireless N router gives me up to 450 Gb/s, but my cable modem supplies me with 50 Gb/s. The increased local speeds are most needed for intra-LAN sharing -- say, bouncing a 4K video from your 2013 Mac Pro to your Apple TV 4. Sometimes a new standard also helps with interference / connection drops / etc.
If nothing else you own is using WiFi, it's not going to be worth it for you to upgrade the router right now.
thanks for the answer. im aware though that nothing but the air has AC on board, but is that what shows up in the option click on the macbook then? its showing the connection speed onboard my mac?
and its really strange, because i have a netgear AC router, and when i hook up the timecapsule to that, and connect through the netgear router, i get 25MB asec. but i can NEVER get higher than 15 MBS connecting directly (wirelessly) to the time capsule. which is strange because they should be the same..