Is there any yaoi manga where the art is really nice?

Not sure on how to imbed links, but I’d recommend Finder and Maiden Rose!

In terms of art, I prefer manhwa... because its coloured.. lol
Manga probably Hasumi Hana, Hinohara Meguru & Kurahashi Tomo sensei works...
But I recommend you read BL manhwa for arts and story line.. For example Wolf in the House & Love or Hate.. The arts and the colours are just so beautiful....

http://www.mangago.me/read-manga/kizudarake_no_hakoniwa/

or umibe/harukaze no etranger

Koimonogatari (Shounen Ai)
http://www.mangago.me/read-manga/koimonogatari/

Anything by Hayakawa Nojiko
http://www.mangago.me/read-manga/endou_kun_no_kansetsu_nikki/

http://www.mangago.me/read-manga/kurayami_ni_strobe/

http://www.mangago.me/read-manga/suna_o_kizamu_hari/


On Doorstep
http://www.mangago.me/read-manga/on_doorstep/

Canis
http://www.mangago.me/read-manga/canis/

I second Love or Hate. It has some of the best art that I've seen for a yaoi series in quite a while. I also really love it because the style is so unique, and it really adds a lot of personality to each of the characters in the series.