Know what I have noticed?
Both the Beta, and RC work very well on wireless, but all interim/daily builds tend to drop signal and not want to connect when more than 20 feet away/on other sides of walls. Don't know if it was on purpose or not, but either way, 'net works better on officially released builds.
PS, with all the builds I've used, when I COULD get signal, I had less than a 3% drop from wired to wireless by way of speed within a standard 3 floor house using 802.11N. (PS: my throughput is massive, not some piddly 1 Megabit connection, 30 Megabit down..)