I had used the Y! Mobile pocket wifi and do not recommend it. On paper is looks great as you can get unlimited open WiFi and use their LTE in spots which lack coverage. You will find their coverage spotty and you will be eating up your LTE data packets sooner than you expected.
My former employer provided me with Docomo’s pocket wifi and it was great. Not sure what it costs now, but it is nice to that you are going to have fast and reliable internet. The difference was noticeable.
Now if you need support or want to cancel your subscription, you need to call their support number which charges you by the minute…and you will be paying the entire time you are put on hold. I forget the exact notice required to cancel even after the three year commitment, but I remember feeling they took advantage of me one last time.
Your experience may be different, but I will never go to Y! Mobile again.