Not for ordinary users. The order is set by the relationship between providers and the serving network, not by what a traveller pays any one seller. A more expensive plan may include more data or different speed terms, but it does not move you up the queue at the tower.

Several things can be true at once. Your friend may be a direct customer of the local network and therefore higher in the order, may be attached to a different network or a different cell, may have a handset that supports different bands, or may simply be using an app with lighter demands. Standing side by side does not mean being in the same conditions.

Not necessarily. A local SIM makes you a direct customer of that network, which helps when cells are busy, but the result still depends on how well that network covers the places you go and what speed terms the plan carries. In some countries buying one also requires registration with documents. Weigh the hassle against the likely gain.

Refund conditions are set by each provider and stated in the terms of the plan you bought. Speed reduced by local congestion is generally not treated as a service defect. A profile that never worked at all is a different matter and should be reported. Message us on LINE at https://lin.ee/skDPoNx or email esimonline.asia@gmail.com with what you are seeing.

Sometimes, because it forces the phone to search and pick a cell again. If the handset was clinging to a congested or weak one, starting the search over can find something better. If every cell in the area is equally busy, toggling changes nothing, not because you did it wrong but because there is no better option available at that moment.