Tomoe River 52 remains a top favourite - I have a couple of notebooks left, so should have it for a while. Have a couple of TR68 notebooks as well.
Cosmo Air Light is a close second - brings out ink properties beautifully and can take a lot of abuse.
The best value for money I've found though has been the Nakabayashi Logical Prime notebooks. The paper is fantastic, and the notebooks are priced decently.
Hobonichi notebooks and planners are all Tomoe River. So are Endless Recorder notebooks. Galen also has notebooks in TR. Now is a good time to get TR - it is still available in many places :)