The original poster asked about tablets. My only tablet is a 2 year 2 month old iPad 2. It has worked flawlessly since new. I keep thinking about getting a new one, but my old one works fine. I have had exactly zero issues with updates and like the new IOS7 quite a bit. I have played with a Nexus 7 and it is a slick 7" tablet that costs next to nothing and has a very good screen, as does the iPad 2. By far the iPad is a nicer looking device. It is "jewell like" in appearance. The Nexus 7 looks like it costs a lot less.
In my humble opinion the key with tablets is having apps you need/ want. Apple has a lot and so does Android. I have the Allstays iPad ap as well as the Android Allstayes ap on my Android phone. Both work well. Windows tablets so far have a lot less apps.
On the other hand regular computers come in Windows, Linux, and Mac flavors. I have used all three. They all work and have advantages and disadvantages. Windows big disadvantage is that it's OS gets slow after a year or two no matter what you do to clean defrag and so on. MS has never fixed this issue as they have no motivation to do so and it is in their interest for people to need a new computer more frequently.
I currently have three Microsoft laptops. I Vista, 2 Windows 7. The old Vista one still works fine as my wife hardly has ever put any programs on it. I do have to de virus /spy it. It has Norton on it again and is staying pretty clean. Firefox got infected by a Trojan not too long ago and I just could not get rid of it. So removed FF and put in Chrome. Problem solved. My 3 1/2 year old Sony W 7 laptop was a high end machine and I have used it a lot. It is pretty slow now and to improve it much would have to re-install Windows. A royal PITA. My 2 year old mid range Toshiba works pretty good still. Somewhat gummed up, but I have never put a huge amount of programs on it. I also have a seven month old Mac Book Pro. All solid state. Without a doubt the best laptop hardware I have ever owned, by a mile. Apple makes superior hardware. IMHO better than anyone else. But it has Apple OS. This is fine for many things but not so great for work that uses Windows documents like Word and Excell. And some /many programs will not work on Apple OS. I know about boot camp. But why add something I know to cause problems to something that does not have them. In the less than a year I have had this computer it has run flawlessly. No anti virus or anti spy software on mine. No problems.
I have also used Ubantu Linux on a couple of computers. It works quite well. Free. But most programs will not run on it. Hard to find good photo editing software for it that is easy to use like Picasa. The Libra Office works slick though. Better than the Apple stuff for MS docs.
Google also makes sort-a laptops. They are only on line. These are very limited machines.
All this stuff is valid. None junk. None perfect. The best tablet might be an iPad with Android on it. And the best laptop might be a Mac Book Pro with MicroSoft W 7. I own stock in all of them. They are all making money.