It depends what type of person you look and what style of cloth you wear. If the rimless reading glasses match your well and you wear properly, it will look smart on you. If the rimless doesn't suit you, It may make you look even more worse. So, you shall try on and choose the best suitable one.
Personally, i think nerd eyeglasses may look smarter and more intelligent.
You will get different opinions from different people. In my opinion, wearing rimless reading glasses do make people look smarter. Rimless reading glasses are invisible on the face due to the rimless design, thus they are not so obvious that people can hardly notice the glasses on the face. People with rimless reading glasses make their faces look more delicate and they can try any outfit or accessories together with the rimless reading glasses.
As far as I'm concerned, some people will look scholarly wearing rimless glasses, but some will look prim on them. In most people's impression, the learned are wearing rimless glasses, so it seems that rimless glasses are the symbol of that kind of people. I do think that it is better to get a pair of glasses that are fit you most according to your eye conditions. Protecting your eyes is the most important thing. There are full frame glasses semi rimless glasses and rimless glasses. You'd better get a pair of glasses according to your vision problems.