Wow, TTT, those is some unreal 'speeds', I'd probably give up gaming -- please don't you do that though. 
Ah yes, we always test the speeds several times before hosting (and not-hosting), simply refuse to inflict that on others on our host. It just seems like some people just get lags from either end, but we've even managed to some friends in who never could connect to many others - but then again, e.g. howyummy seems to be unable to join. 
As for Turtle Beach headsets, isn't it very possible you guys all have different models. There is a lot of variation within that brand alone. If i ever said 'duh', this would be that time.
Here is my experience:
I read through several reviews before buying any headset, and the wireless ones got worse grades for everything throughout the line, for that brand and some others (read also: less features, which is ridiculous for assumably newer tech).
The wired Turtle Beach PLAs we have, are my own favourites;
- A nice long wire, and soft foam on both ears; I will never use those models with just one-ear-speaker+hard clip on other side - that idea is DOA if one wants sounds from all sides.
- PLAs sit snugly and aren't too hot due to the foam -- I hate those fake leather/leater ones! They make me sweat. (I'm sure some will say the opposite, but this is my opinion, so I'm voicing it as is.)
- The sound quality is good, and my favourite & absolute must: you can adjust the game sounds and chat separately.
- The newest pair was also 23 eur on sale (normal price here 40eur, everyhing is ecking fuxpensive in fhis country). Our older set is about 1 year old, and there is no sign of any wear or tear.
So, I for one have been happy with our Turtles - and not ashamed to say that as a gril, I'm picky about the comfort level.
If there was one thing I could change, I'd want this exact same model wireless, but it doesn't exist. And now i don't have to charge them up or worry about battery life. Wish you'd see how much I often exercise/flail/sway/duck during gaming, and I still manage the wire just fine.
Oh yeah, I am not affiliated with them.