The road may be not quite so tough since you already have a d300. For me, the d800e was my first DSLR - and I sometimes find myself fiddling with issues like long exposure noise reduction which for others is a regular feature they know from their prior cameras. I would say, even if you treat the d800 like your d300, the pictures will have an improved technical quality - not only with regard to details, but also the dynamic range! And if you are going to carefully use that wonderful tripod of yours - well, I would like to see some pictures when they come along. Have a good intellectual journey with this camera.