I think it is smth between 1/35 and 1/48, I can take a picture of 1/35 tank next to it, if you are interested.
Otherwise, those WH40K models are fun to build. Really easy to assembly, it can be done in a couple of hours and then you can experiment with painting and weathering without fear that you ruin a sophisticated build.
The disadvantage is that the kits are quite expensive comparing to the level of detail you get from usual 1/35 models. Unless you are a fan of WH40K...