Sent mine to Apple a couple of weeks ago, got it back fairly promptly with a nice patronising letter telling me that it had been tested extensively and met apple's requirements for useability and functionality and my problems were likely due to it not being charged fully or because I was using an old version of iTunes. These are both are untrue in my case and as we know is complete horse s#!t anyway, the lowest my battery has been since owning the device is 50% so by that rationale, an iPad is unuseable when the battery is half empty???? I don't think so.
From everything that I have read, tested and deduced it seems there are iPads that work well and iPads that don't, it seems that they cannot maintain manufacturing quality. My neighbour has an iPad 2 16gb ios 5.0.1 which we tested here and it worked like a dream, gets great wifi reception in every room in the house, didn't drop once; mine is an iPad 2 64gb 5.0.1 and I struggle to get reception in about 50% of the rooms in the house and unless I'm in the same room as the router or the room next door (simple stud wall), down/up load speeds are severely reduced. I borrowed an iPad 1 from a work colleague and his suffered as well, as it does in his own house (though he blamed the cruddy sky router).
If I sit my laptop in my kitchen, I can 'see' 5 different wifi networks, with the iPad I can barely see my own (therefore it's not just my router that's the problem). And before anyone says that could be the problem, I've made sure that mine is operating on a channel far enough away (they are all on 11 and mine's on 1). I've extensively used inSSIDer to monitor the wifi signal in my house, in the same room as the router I get -25 db reception, the worst part of the house has -60 db so I have a strong (enough) signal throughout. I can also see that there's no other phones / baby monitors etc causing interference on the 2.4 Ghz bandwidth.
TBH if I had bought the product myself it would be on eBay right now but since it was a present from my wife, I feel I should try and resolve the issue (you can imagine how pi$$ed off she is about it all!) Also Apple's real sledgehammer is their products useability and tactility, though I have to agree it's a lovely product to 'hold' it appears that software updates are making the products worse. Whereas my iphone 3gs used to be snappy as you like, it's now becoming really quite slow since I left iOS 4.xx behind and updated to 5.0.x e.g. (2 - 3 seconds to enter settings), (5-6 seconds to 'wake ' the phone when playing music) etc. Also a simple thing today, tried to set hotmail up on the ipad and unlike the phone, there's no advanced settings to enable the ipad to delete messages from the server, so had to delve into the forums and find a fix using Microsoft Exchange, fairly simple to do but that's what I expect from the ubuntu linux netbook I use or a 'droid device, but absolutely not from iOS. At their price point any Apple device needs to just work.
I would add to the list of routers that work / don't work but feel that it's a bit unfair to the router manufacturers, as it isn't their products that are at fault. For info, mine's a DrayTek Vigor 2800 G, an oldie but a goodie and as to whether it works or doesn't work, I can't really answer as it worked a treat with the with the iPad 2 16gb I tried, it works (kind of ) with my iPad 2 64gb and (kind of) works with the iPad 1 32gb I borrowed........ go figure. I only have a phone point in one place in the house and don't really want to rewire the house just so I can get reception on the iPad, I have some cat 6 that runs to a central location in the house (use it for carrying HDMI signals from the sky box to other rooms), so I temporarily used it to place the router in a central location and as you might imagine it basically just shifted the problem areas to other parts of the house. I've tried a high gain antenna (worked a bit better, got coverage in one more room), sent it back and changed it for a directional antenna (now can use the iPad in 2 more rooms), the next step is either a powerline wifi ap adapter and a new router (probably about £100 all in) or just another wifi router and bridge the network which is a bit of a faff having to keep switching SSID's depending on what part of the house you're in.
Sorry for the rant but forums are for sharing experiences, findings, knowledge and resolutions and I've tried to cover it all in the above.
