A low-poo is just a sulfate free shampoo. A lot of them have coco betaine (aka cocamidopropyl betaine) a gentler cleanser than sulfates.

Many curlies follow the curly girl method which promotes going sulfate free by washing your hair only with conditioner (cowashing). The reason many curlies also avoid silicones is that they are not water-soluble and you need to use a shampoo (sulfate or lowpoo) to remove them from you hair. Conditioner isn't enough.

So basically if you want to use silicones, that's fine! Just make sure you are using some kind of shampoo to avoid buildup.