Sorry, lost Chinese translated reply, don't have time+energy to redo Chinese . . .:
1. $10/4G is only for existing Fido postpaid (phone) customers, options: a) join Fido postpaid, + sign up data plan, + cancel postpaid; OR b) run around to look for Fido reseller who is willing to sign u up for data plan only (not supposed to but few Fido resellers were able and willing, hard to find)
2. Many people use this data plan for years, may be up to 6/7 years, got up to 3 free tablets. Fido renewed data plans in past, but no guarantee that Fido will continue to renew (most people don't have Fido postpaid)
3. As 家园小千 explained, most people use this data plan with VOIP phone (Fongo/Textnow/etc). As VOIP phone is not 100% reliable, it is suggested to keep a mobile plan also, such as 7-11 Speakout ($25/yr).
4. Most people put data SIM into mobile phones. Some would buy dual SIM phone to have phone SIM in the same phone.
麻烦嘛?