Hi Joe,
I own a Sony Vaio Multi Fit, and it has been having this issue since day 1; fortunately Sony provided me with a little usb wireless micro adapter (Belkin SURF N300)and so I am able to see the huge difference in terms stabilty and strenght of the connection in every condition (infact the Sony help-desk told me that this is an already recognized issue and Sony/Intel are working on it)
Here are my answers:
1. 2.4 GHz (my router works only on 2.4 GHz band, it is a Netgear DGN2200 updated to the latest firmaware)
2. Win 8.1 Pro 64 bit
3. I use it only at home
4. About 6.
5. I don'play online so my experience is just slowdowns in loading pages, high buffering times for video streaming and, of course, frequent connections drops (as i mentioned before this doesn't happen with other pcs or even inserting the Belkin little usb wireless micro adapter...............)
6. Tried disabling Bluetooth, uAPSD, VHT. No effect.
7. Sony Vaio SVF13N2Y9EB.
8. Yes, this unit is only 2 months old and has not been modified in any way