It's a 'meh' from me.
It's not bad, as far a as a reflex game goes; plus nice visuals and a quaint little story, but it's nowhere near this ball-busting revolutionary reflex test it advertises as.
Most of the obstacles in the game rely on trial-and-error to move past. Take the farmer, for example; awesome, you know full well you can chuck a spear through the guy and be done with it; but what about the Spartans? If you're super-quick and all intellectual like, you can put two and two together and see their massive shield and decide a spear would be useless....and then what? There's absolutely nothing about their design (especially with a RAISED SPEAR) that suggests jumping is the way to kill them, but it is...then why can't you jump the farmer? His own weapon is even lower than the Spartan's, yet he has no issue goring you even as you try to leap over him. And the rider, yet again, how in the world was blocking supposed to work? Thus far it hasn't worked on any weapon except arrows. It doesn't stop the farmer nor the Spartan; my first instinct was to duck UNDER them, completing this type of weapon-trifecta you have going on...nope. Oh yes, and the arrows. Ducking doesn't stop arrows from the front, so why does ducking cause them to miss when coming from behind? There are no visual cues to go on, so you only have to guess your way through and hope it works out.
Oh, I mentioned the lovely visuals, unfortunately those also have a knack of screwing you over; though this is a more minor complaint as you can avoid it just by being more watchful than usual. The branches that knock you off your horse are the exact shade of pink as the branches in the background, so when your attention is drawn this way and that through obstacle after obstacle, it can be very easy to simply miss it and be forced to restart the level.
My final gripe tends to tie the main point in, that the screen is so small and your character's cooldown is so slow that you only have one shot to make things perfect. That is to say, if I see a character at the start of the screen and react quickly, as the game has been training, by throwing a spear only for it to turn out to be a Spartan (or, which has happened repeatedly, farmer, another farmer, then a Spartan, or even vice-versa), that's it, I'm done. My character's cooldown is so slow that I can't recover from throwing it fast enough to jump. I just have to sit back and insult myself all while watching my character's drawn out death screen. This is the real nail in the coffin. Trial-by-error WORKS, but it only works when it's fair, and it's only fair if you have a large margin for error. It only works if I'm introduced to a new threat and can try numerous different tactics before it's in the danger-zone; it absolutely doesn't work if I only have one shot or else I have to restart everything. This becomes especially damning in later levels where the obstacles come at you so fast that a single mis-step makes you restart. And yeah you can argue "Oh, but it's a reflex game, that's the point! You gotta have quick reflexes! And once you're introduced to a threat, there's always some warning as to what's coming, giving you ample time to remember how to react!", but therein lies the issue. At that point it stops being a game featuring reaction time and instead features your memory, you see?