I was looking for a good timer that I could use for HIIT (High Intensity Interval Training). I hated having a stopwatch in my hand because I had to stop doing the workout in order to read the time. The idea of having a timer beep and or vibrate at the end of each interval sounded extremely convenient. My only complaint (which for me is a big deal because it basically prevents me from being able to use this product) is that the ONLY settings for the set length are :60, :90, or :120 and the settings for the rest length are :30, :60, :90, or :120. The problem with this is that the most effective workouts for me are along the following intervals: :30 set lengths at 100{60f78fc10f9d225dae0ba0255c415eaf093f5a3220b43cdf3df82aaf7b5f9e5d} effort followed by :45 sets of light jog (rest). I guess it’s my fault for not reading the description more closely. I think for an extra -3 you should be able to purchase an item that offers more variety in your options. Also, guys with big arms would have difficulty wearing the included armband. At the maximum circumference, the armband is pretty uncomfortably tight on me and I wouldn’t consider my arms that big at all.

I use it for interval running.

CON: It only goes 10 "rounds", or 10 sets of 2 intervals so I have to reset it every 20 minutes. Not so bad during a race (a reminder to hydrate and look around) but when I am in a training group of people , it can get a bit more complicated. You can’t set it ONLY to vibrate, it vibrates AND chirps

PRO: It is MUCH more rugged than a GYMBOSS and MUCH MUCH more waterproof. I have run it under a faucet and still works. Easy to set, easy to start. No having to press more than one button. Vibrates more and chirps quicker. Comes with a strap that you can put it just on your arm. Cheaper too.

I like it but if you are looking for something to stay in sync with other people’s Gymboss, it won’t work. If you are looking to be the only interval timer in the group or just for yourself, I recommend it.

I bought this hoping to use it for HIIT sessions on an occasional basis.

The pros:
It’s easy to set. All the controls are well marked and it’s easy to understand exactly what you’re doing.
Comes with a strap for your arm with a “pocket” for the clip to go on.

The cons:
I bought a timer with a vibrate feature so as not to disturb others with the alarm. There’s a way to silence the vibrate, but not the beep, which is loud.
The device is a lot bigger than I expected. It’s quite thick, and fairly large rectangle. I really want something smaller.
The strap doesn’t really help much if you have to do much resetting (changing the number of sets or the timings of the intervals/rest periods).
The interval and rest period settings are limited to a few. If you don’t like those, you’re out of luck.

Potential improvements:
-make it smaller!
-ability to turn off the beep, which is quite loud.