Outside of complaints about a hotter operating temperature, some Wi-Fi gremlins, and wicked fast LTE wireless connectivity that Verizon (NYSE:VZ) customers soon discovered is capable of burning through a 5GB monthly data cap in about half an hour, Apple (NASDAQ:AAPL) has to be pretty happy with its latest iPad. Especially after announcing sales of three million units in just its first weekend of sales.

There’s one area that’s been a sore spot for some Apple critics, though, and the chorus has become a little louder with the introduction of the new iPad. Tech Republic and ifixit are among the websites that come down on Apple for making it increasingly difficult for owners to repair the device, noting that the new iPad is even tougher to open up than the iPad 2 — which was difficult in itself, requiring a heat gun, numerous plastic picks, a prying tool, suction cups and a very steady hand.

There are two schools of thought when it comes to mobile devices such as smartphones and tablets. TechCrunch recently wrote that Apple has a strong case for making it as difficult as possible for consumers to open up its iDevices, pointing out that from a business perspective the practice makes sense. Making iPads and iPhones tough to service ensures that customers will upgrade every few years.

Offering replacements for faulty devices instead of repairing them is cost effective for Apple since it means Apple Stores don’t need trained technicians and specialized equipment. Sealed units using glue instead of clips and screws also allows them to be slightly thinner and improves aesthetics.

A source of frustration

Environmental watchdog Greenpeace International calls out Apple on the issue, awarding the company high marks for energy efficiency and recycling efforts, but grading its product life-cycle strategy poorly.

In a response to TechCrunch, ifixit argues that by making iPads so difficult to repair, Apple is being shortsighted. Devices that aren’t repairable are not only an environmental concern, the practice risks alienating customers who feel forced to spend the money to upgrade to a new device because of something that should be easy to address, like a worn battery. Yes, Apple does offer a battery replacement service, but it costs $99 (plus shipping) and the company simply ships a replacement iPad, which may be an issue for people with custom engravings or a personal attachment to their device.

Accidents waiting to happen

There’s another angle to the issue as well: user experience. As someone who has worked as an Apple repair technician in the past, I’m reasonably comfortable in pulling devices apart. But I’ve seen many examples of what can happen when a device — such as a MacBook Pro — is reasonably easy to open up. Some people will embark upon do-it-yourself repair or upgrade projects and cause extensive (and expensive) damage to their computer. Stripped screws, snapped cables, broken casings that are super-glued back together, and electronics that had been shorted out were common. Faced with the repair bill, there’s a tendency to lash out, including going online to vent about the product’s apparent shortcomings.

Another way to approach the issue is to think of the iPad or iPhone as an appliance instead of a mobile computer. People became accustomed to the option of opening up a computer to replace components, but most would think twice about disassembling their HDTV to attempt a repair. Automakers have been taking this approach for years, with many engines now covered by cowls to prevent owners from tinkering and some manufacturers like Volkswagen AG‘s (PINK:VLKAY) Audi going so far as to eliminate the oil dipstick.

While adopting a policy of “protecting” everyone to prevent a few from coming to harm may not be the best way to do things, it does make sense in many ways. Like it or not, Apple is expected to keep going in that direction with the expectation that the next iPhone will likely follow the iPad example and feature a sealed case instead of removable screws. Three million new iPads sold in one weekend says most customers aren’t that upset with the policy.