I watched both.
About To Heart: Very very very good and underrated show, but only if you like this specific genre (which I amazingly like).
To Heart 2 and Remember my Memories: crap aside for the Zettai Ryouiki and Multi.
Kimikiss Pure Rouge - It had a lot of potential, but nothing really happens until episode 19, and by then you will have a very good sleep.
Hot girls though (I especially like Mao-neechan and Futami, although both are bitches).