I use Minuum and have Swiftkey, although I have to say I never liked it as much as swype or the google keyboard. I used to use Fleksy full-time because it just seemed way more responsive that Swiftkey and the gesture typing is pretty awesome. The two biggest pros for me are as follows:

1 - Small keyboard makes it hard to look at the keyboard itself as you type forcing me to actually touch type on my phone. This has allowed me to catch way more typos as I write and has also helped my writing as I can focus more on the flow of the words than on the act of typing.

2 - Screen real estate. I know that phone screens are huge, but if you want to write something longer being able to read more of what you have written without having to constantly stop and scroll is great. Responding to emails and incorporating details from prior messages is much, much easier.

Cons:

1 - I find the space gesture to sometimes result in the backspace gesture being selected if I go too quick. Compared to the speed and effortlessness of fleksy this is much more finicky.

2 - The swipe up/down to pick different word corrections from fleksy is not present meaning that choosing a different word completion requires you to leave the "home row" and click on a small target. Way less convenient.

3 - The swiftkey style "start typing and just select completions to finish the sentence" style doesn't really exist, but most of my sentences weren't as canned so I didn't really use this feature.

In summary, I use minuum and like it a lot. At most you've lost like 4-5 bucks or something or like 1/2 of a footlong sub. So you really can't go wrong by just trying it out. I would also recommend fleksy if you don't like minuum as I find both to be better than swiftkey. If minuum could grab some of the fleksy features I mentioned above it would be unstoppable.

I went from using SwiftKey to Minuum. I would say SwiftKey has better prediction, at least for predicting the next word. Minuum isn't very good right now at predicting the next word you want to type based on the previous words, though I think it has been improving. However, I think on average I probably type at about the same speed on both because Minuum allows you to be much sloppier and there is only 1 dimension.

Overall, the only real advantage of Minuum currently is its smaller size which allows you to see more of the screen... which is point. SwiftKey has more languages and currently allows for faster switching between 3 of them. And since its been around for longer is probably slightly more polished (less weird behavior when encountering weird input fields).

Oh, the other thing about Minuum is that people who haven't used it might have trouble borrowing your phone :P

I tried. Swiftkey is very resilient to errors, so I just swipe the finger over keyboard quite vaguely and know it will cope somehow, I have to be much more precise for minuum. Guess that's because of one lost dimension. Also, my phone is huge (htc one) and it feels unstable when hold it low enough to type where a spacebar used to be.

So, sorry guys, refunded.

They're both predictive typing, so they both fall on their face when it comes to two things. Proper nouns and slang.

Whenever I try to write one of those two thing (often, think email addresses, friends names , "yo", etc) I have to fall back on regular input.

With swiftkey, this means just going back to pecking. With minuum, it means going into a menu and switching to minuum's full sized view or long pressing each region to get a zoomed in view of the keys around there to pick out the one I want.

The compactness of minuum is great, though. And when I'm entering non-proper nouns it's as fast as any keyboard (given a few days to adjust).

I paticuraly like the "swipe left for space" function.

It makes me want to try even more radical keyboards. Maybe something chord based.