>>1663259Like >1663284 said, the boorus and exhentai/g.e-hentai are the best.
I used tog get my images from gelbooru and a thread on the neko-sentai forums bit with time I switched to sankaku and pixiv. I use exhentai for doujinshi and manga.
Gel/danbooru are the greatest when it comes to number of images but sankaku isn't far behind.
I've been thinking about building my own booru as well.. We'll see