Slow AE2500 network adapter

Since you are on a 802.11g connection, about the best you can expect is 20Mpbs. Even though it connects at 54Mbps, due to overhead (error correction, etc) you lose more than half the speed. Of course as you see, as you move further away from the router, the slower it becomes. This too is normal.

I think your wireless adapter is working normally. If you want faster speeds you'll need to look into a dual-band 802.11n router. Or upgrade the entire thing (router and adapter) to 802.11ac.

Your test prove that 802.11g isn't able to max out your internet connection. So the short answer is yes, an upgrade is worth it. Now whether going to the extreme of replacing your wireless adapter and the router is necessary depends on your needs. 802.11n is plenty enough to maximize your internet connection. You already have a dual band wireless adapter capable of 802.11n. You could get a 802.11n router and be done with it. Now if you do lots of LAN side data transfers between different computers (big files) then 802.11ac might be worth it.

My suggestion is get a decent 802.11ac router, nothing too expensive. All AC routers support dual band and 802.11n. Then if you ever decide down the road that you need the speed of AC on your network, you've already got the router so all you'll have to replace is the wireless adapters. 802.11n will give you slightly better than 50Mbps, so that will cover most of what you were getting connected via ethernet. However with everything wireless your results vary with the distance between the router and the client and how many obstructions are in-between.

So the short of it is I would get an AC router in the $100-$150 range from a manufacturer you're comfortable with. For me that would be Linksys (now owned by Belkin), or Net Gear.

One thing to note, the 5GHz band is usually better speed wise. However it doesn't penetrate obstructions (walls, floors, etc) as well as 2.4GHz, so you may find in some areas, the 2.4GHz band (still capable of 802.11n) gives better throughput. The other thing about the 5GHz band is that it usually isn't as congested. Meaning everybody and their dog has a wireless router transmitting on the 2.4GHz band, so you have to contend with neighboring router interference.

Funny you should ask about Powerline adapters, I was just researching them. I remember when they first started, they sucked. However in all the research I've read, it seems that they have sorted out one of the biggest problems and that's interference from noisy devices on your electrical system. Microwaves, dryers, stoves (sometimes), could cause havoc with Powerline. But as I said, these seem to be most fixed.

That said, from my research, performance really depends on the wiring in your house. The older the wiring or more natty it is, the less speed you will get out of it. It's also somewhat like wireless, the farther away the powerline adapter is from the one that connects to your network, the slower it gets. However it is impervious to obstacles like walls and floors, just the condition of your wiring and the length of wire between the adapters affect it. As for which products are best, from my research, AV2 500 isn't much better than AV 500. However since AV2 is newer, they are more expensive. If you go this route, find a product your interested in and find a review of it online. Powerline can be faster that wireless (aside from the caveats I've already mentioned), but it can get pretty expensive to expand it to more device later on. However using Powerline to supplement a good wireless setup can have it's advantages. One instance would be to have a good stable connection to your AV system for streaming stuff like NetFlix to your TV.

If you plan is to go with a new router, I would definitely go on the less expensive end of AC unless you like having the best. However the best is likely going to cost you north of $200 just for the router. Something like Linksys' new WRT1900AC fits this bill, but it'll take a lot of bills out of your wallet. If you want a suggestion for a model just let me know. And of course if you have to buy at least one wireless adapter, you might as well get an AC adapter. It's really up to you. Do you and your son transfer data back and forth between your computers? If you do, this is where having AC on both will really shine assuming you both have decent connections to the router from each of your computers.

Actually there are Powerline adapters that have both a ethernet connection and wireless. Think of the ones with wireless as a wireless extender. Of course as with anything wireless, the closer you are to it with the least amount of obstructions, the better.

If you only ever plan to have two computers on your network and no other devices (Wi-Fi enable phones, TV's, Blu-Ray, etc, etc) then Powerline would be the way to go. However if you have the two computers, and phones, and yadda, yadda. It would be better to stick to Wi-Fi.

As for myself, I'm looking into Powerline to extend my Wi-Fi and improve my connection to my Samsung Smart TV. I will get two kits (so 4 Powerline adapters), one obviously to connect my router to my electrical system, one to my TV, and one downstairs which will be connected to another router setup up as an Access point. Presently I have my TV connected to my wireless so that I can watch Netflix. For the most part it works OK, but every few minutes or so, the audio skips, the video is fine, just miss a split second of audio. I thought maybe adding a more stable connection would help this. The Powerline adapter in the basement is to extend the wireless range (my main router is upstairs) where the signal is weak. My one son's room gets a very weak signal, and since I have a spare router, I thought it would be the perfect use for it. I'll have an extra adapter left over for some other project or a backup in case one goes down.

I was looking at either Linksys (PLEK500) or ZyXEL (PLA5205KIT, or PLA4225KIT), although these ethernet only. I can't speak for TP-Link, but Trendnets stuff is usually pretty low end. That said I have no experience with either brand.