JKarczmit- if you look at the descriptions on Music Direct, the deluxe LP version of LZ 1 is three LPs, two of which are out-takes or previously unreleased material. LZII and LZIII are two LPs each, and the description says the second LP in each is the previously unreleased stuff. No suggestion of 45 rpm or one sided pressings. I think we already read that these were taken from digital files.
Low, as to the Classics being the best representation, not sure. I own several, including the 45 rpm set of LZI, as well as the 45 of Stairway, along with a 33.3 of LZIII from Classic. Haven't heard the 45 of LZII, but would be surprised if it has the impact of the 'RL.' As mentioned, the best pressing of LZI I've heard was a first press by Monarch that I haven't been able to source; the one much loved among Hoffman devotees is the Piros 74 remaster of LZI (which I do have) and it is very good.
I'm not dumping on these newest releases- I've already pre-ordered the deluxe editions and will see how they compare to the many pressings I already have. (And, as I may have mentioned, I'm not absolutely against digital re-do's- the Tull Benefit on vinyl (UK track list) with the Steve Wilson remix sounds better to me than my first UK and US pressings, though that album was very muddy). If these prove to be good, they will be a bargain, given the cost of the Classic 45s and some of the early original pressings.