After being true to Casio (WS110H model) for more than 20 years, I wanted to test one of these Timex watches of the "famous" Ironman range ... A reading technical characteriscs the T5E231 shows seemed to match my expectations: I did athletics and so I need a lot of memory capacity to store the time of my training sessions; I also need a double count-down to be able to simply manage to split my sessions. Upon receipt of the said show, the first disappointment: the quality of the instruction manual is poor; is folded cigarette paper umpteen times ... it changes me the instructions provided by Casio connected; Moreover, the explanations are not very clear ... luckily I've handled this type of watch! Then in use, this watch is really not the most practical: - Ergonomic adjustments really poorly thought; we end up losing it! - Ergonomics of use is crap, especially in stopwatch mode. For example, it was fashionable to have the START and STOP button at the same place. The button for storing the split times (split time) is super sensitive, a little too tight enough to handle the trigger! The associated audio signal to intermediate time is almost inaudible, so it must always take a look to see if a time has been saved. If by any chance, an alarm sounds when you press the lock button of an intermediate time (eg. Following the expiry of a count-down), no time will be stored! Consultation of stored time is not the most intuitive ... as well as their removal. Finally (but not limited to) the sound signals emitted by the triggered function (start, stop, split time) are all identical (and virtually inaudible) so it should always visually check that the watch has been (or not !) consider! Conclusion: I who believed that American knew design products, I am disappointed! For ergonomics, better to turn to the Japanese ...