Fuel usage: With the standard configuration, fuel usage comes close to HOST's, but is not identical. PHost also offers an additional fuel consumption model (UseAccurateFuelModel) which accounts for the fact that ships get lighter by burning fuel, therefore they consume less fuel. See Fuel Usage formulas.
Zero-Fuel Movement: In PHost, ships without fuel can move at most one light year. In HOST, they can move as far as they get.
Movement through Mines: When the tower runs on a mine and explodes, the towed ship can escape and use the remaining time for moving towards its original waypoint if TowedShipsBreakFree is enabled.
The value of HullTechNotSlowedByMines determines what happens to ships which get damaged in a minefield. The mine hit odds can differ for each warp speed (MineOddsWarpBonusX100 etc.)
Gravity Wells: It is not entirely clear from HOST documentation when and how gravity wells affect ships. In PHost, the conditions are configurable (AllowGravityWells, AllowHyperjumpGravWells). The conditions for gravity wells, and their effect, are documented under Gravity Well formulas.
Intercept: HOST restricts intercept to ships closer than 200 ly, to prevent blind intercepts. PHost allows you to intercept everything you see through your result file (and only that).
PHost implements intercept in a different way than HOST. With circular intercept, the meeting point and movement path of the ships will differ. It shall be noted that HOST's intercept resolution has changed significantly between versions as well.
