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The original
The original Samsung Galaxy Note started the phablet craze we're witnessing today and the Galaxy Note 3 is the latest instalment in the Korean firm's supersized smartphones.
Bundled with the S Pen stylus, the Galaxy Note 3 already has an advantage over the G Flex when it comes to handwriting recognition and note taking.
Samsung has also stuffed the Note 3 full of eye, hand and heading tracking technology - so if you don't fancy touching the screen all that often you'll want to check it out.
The Note 3 isn't a great deal cheaper than the G Flex, but it does boast a full HD, 5.7-inch display, an extra GB of RAM and a microSD card slot for expanding on the internal storage making it an all round better offer.
The Galaxy Note 3 is becoming mainstream, so if you fancy a smartphone that's going to turn heads the G Flex is the one. If you just want to get things done then plump for the Note 3.
Unique, in a different way
While the LG G Flex has its curved, flexible chassis the Sony Xperia Z Ultra has a massive screen. Seriously, it's huge - a whole 6.44 inches of real estate makes this device more tablet than smartphone.
That whopping great body is also dust- and waterproof, meaning you can happily whip it out in a thunderstorm or take it in the bath and watch a movie while soaking in the tub.
The trade off however is the Z Ultra's size. It's large, unwieldy and will stretch your pockets to their limits - I found the G Flex tricky enough at times to manage and the Xperia Z Ultra just enhances the issue.
If you want a decent camera on your smartphone you're better off going for the G Flex, as its 13MP snapper trumps the 8MP offering on the Z Ultra.
However if you fancy a small tablet which you can make the occasional call on, and use a normal pencil as a stylus (I kid you not!), then the Xperia Z Ultra may be the one for you.
Copy cat
The LG G Flex is basically a bigger, more flexible LG G2 with a lower screen resolution. The two phones share the same processor, GPU, RAM, cameras, operating system and interface. Heck they even have the same buttons-on-the-back set up.
The LG G2 has two key advantages however; price and screen. In fact a SIM-free G2 will cost you around £200 less than the G Flex, and for that you get a 5.2-inch, full HD display with a 424ppi pixel density.
Compare that to the 720p, 245ppi 6-inch screen on the G Flex and the G2 makes a very convincing case for itself.
I also find the G2 much easier to manage in one hand, while I'm always worried that the G Flex may slip from my grasp as I shuffle its long body in my hand as I desperately claw at the notification bar at the top of the screen.
The G2 can't compete when it comes to battery life though, with the LG G Flex's 3500mAh comfortably outstripping the 3000mAh offering in its smaller brother.
If you fancy a top LG smartphone then go for the G2 - it's cheaper, just as powerful and easier to wield.
John joined TechRadar over a decade ago as Staff Writer for Phones, and over the years has built up a vast knowledge of the tech industry. He's interviewed CEOs from some of the world's biggest tech firms, visited their HQs and has appeared on live TV and radio, including Sky News, BBC News, BBC World News, Al Jazeera, LBC and BBC Radio 4. Originally specializing in phones, tablets and wearables, John is now TechRadar's resident automotive expert, reviewing the latest and greatest EVs and PHEVs on the market. John also looks after the day-to-day running of the site.