Beneficial insects (except centipedes and millipedes) that are not hazardous or annoying are always completely welcome, in my opinion. I usually have lady bugs on my plants during the winter. I have had the little wasps outside every year and, now and then for a couple of months indoors, but I think the spiders must eventually get them. This autumn, all I had was an ant colony in a pot (diatomaceous earth got rid of them) and some yellow jackets that somehow kept getting inside.