Should you go 7.9 or 9.7?

It's one of two big questions facing indecisive consumers who are thinking about buying a new iPad but aren't sure which one to choose.

The new iPad mini, which went on sale in Canada on Friday, has a 7.9-inch screen, versus the 9.7-inch display on the newest full-size iPad.

The other magic number to consider is $170, as in the price difference between an iPad mini and a similarly equipped version of the latest large-sized iPad.

On the low end, a WiFi-only 16-gigabyte iPad mini is $329, versus $499 for the big iPad. The most expensive 64-gigabyte iPad mini, out later this month, is WiFi and mobile network-ready. It'll go for $659, while the latest upgrade of the iPad with the same specs goes for $829.

So is it worth an extra $170 for the larger iPad? Or put another way, will price-conscious buyers regret not spending the extra $170 if they go with the cheaper iPad mini?

The iPad mini's smaller screen brings down its cost and Apple also saved a few bucks by sacrificing a bit of screen quality.

Since the third generation of the larger iPad, Apple has used its so-called Retina Displays, which have a resolution of 2,048 by 1,536 pixels, and a pixel density of 264 per inch.

In plain English, more pixels equal more detail and better sharpness.

Because the iPad mini has a resolution of 1,024 by 768 pixels and a pixel density of 163 per inch, it is noticeably less sharp. Text on the iPad mini has some clear raggedness around the edges.

But it may not be apparent to many users unless they're doing a side-by-side comparison with a larger iPad or another tablet with better screen resolution. In any case, many will find the slight increase in sharpness isn't worth an extra $170 and is an acceptable sacrifice to safe a considerable chunk of change.

For those that envision carrying their tablet around on a daily basis, the iPad mini is a little easier to lug around, with its smaller size and lighter weight. Those who would keep it on their coffee table or kitchen counter most of the time might not appreciate the smaller size as much.

Even starting at $329, Apple's latest tablet isn't exactly dirt cheap. In fact, when compared against some similar-sized competing tablets, it looks expensive.

Google's WiFi-only 16-gigabyte Nexus 7 is $209. It has a slightly smaller seven-inch screen but is sharper, with a resolution of 1,280 by 800 pixels and a pixel depth of 216 per inch.

Don't let the price deceive you, the Nexus 7 is a quality product. It's speculated that Google may be selling it at cost in an effort to challenge Apple's supremacy in the tablet market.