Analog Lab have a lot of sounds. Most of the presets does'nt use a lot of CPU, but yes some can put some load on a CPU, just like some other vst's use more or less CPU. So you have to be more specific.
Keep in ind, that analog Lab use Presets coming form many different applications.
Which tips was you looking for?
Perhaps i also have some different tips, if you mention specific presets.
You mention Repro-5. Arturias Prophet 5 presets in Analog Lab does'nt use more CPU than that does - actually it use less, just to give an example.