The FX and devices in the strip are simplified versions of the standard plugins included. Using the full plugin as an insert will present you with the full metering. No doubt you’ve figured that out already. The point is, as with virtually all plugins, they require a certain knack, or “getting used to”. Once you get past the textbook settings for ratio etc. the rest is experience. After a while you learn to know the specific plugin, and how it should sound - the indicator lights are not so important (similar to some mixers that provide full metering for all channels compared to one that only provides a single LED indication per channel. When scanning the channels, all your really looking for is to see that all channels are at a decent level and that none are clipping which can also be accomplished with a single led glowing green or orange and red, and the full metering is somewhat superfluous).
To reiterate, these plugins require a certain amount of experience, which can only be gained in practise. Using the full plugin initially will help you get accustomed to the effect.
That the FX in the channel strip use the same algorithms etc. as their standard plugins I should think the processing power savings will be slightly better for the strip controls (especially less graphic power) , but perhaps not too dissimilar.