I haven't technically made an ownership switch, but I have driven both the E70 X5 4.8i (mostly optioned-up) and we have a X3.

The X3 will be nimbler and feel a bit quicker on its feet. I mean, it weighs half a ton lighter, so that's a good start. It can also get 27 miles to the US gallon on the freeway, regardless of what the window sticker says.

The interior isn't as luxurious as the X5 and nor does it have many features. I is after all, based off the E46 3-series. But it is roomy enough, and fairly comfortable up front. It's a bit "no-frills" for a luxury car, but everything is well-laid out and purposeful. No iDrive or electronic shifter.

The size is just right in the city. I can dart in and out of traffic as I would a smaller car; and parking is not difficult.

To its merit, the X5 does ride better. It's a longer wheelbase, smoother, and still fairly competent in the bends. There's also the allure of a V8. And if you're into gadgets and must have the latest technology, the X5 does it much better than the X3, which is based off technology from 1999.

I like the X3 a lot, and at the end of the day I'm not a big car fan. I don't like big vehicles, but the X3 is about as nimble as SAVs (or SUVs) get. I'm one of those who are bit nostalgic about the older BMWs, so I like how my X3 reminds me of the previous 3-series.

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2014 Mazda 3 GT: Ø Consumption: (click for details)