I'm definitely not saying PV is an egregiously bad weighting system, let alone that it's anywhere near as bad as BV.
But I do think some types of units are better than their PV would indicate (and some are worse). Light, fast units especially, or units with unusual abilities that are especially powerful when combined with their stats. Take a look at the PV for LAMs, for example. With their Airmech movement options and the corresponding defense bonus they get from speed, they're considerably better than 'Mechs of the same PV.