Really good for first time. As spud already mentioned, you should've wear it much more.
Plus little advice, plan this good before doing, focus on real tank and think what and where would wear more and where less, as well as what direction would the wear be. Maybe use softer brush as well.
From interesting stuff... Russians didn't paint white camouflage on wheels, snow would do that for them
thanks for all the comments and advice lads, i scratched at the white wash a bit more and while i possibly should have removed more of it im quite happy with its look and ive done some more blending of the grime streaks as advised by spud, i will do some smoke at the exhausts and then onto the base, thanks for the hints Hovek and i just painted the whole thing white, i found a pic of a whitewashed isu and the wheels were done but as im going to be covering the whole bottom of the tank in quite a lot of mud very little of the wheels true color will be seen, as its my first tank im fairly stunned at how well it has come out for me and while it could be better it has been very good fun and ill deff consider doing another one in the future, ive used techniques which i had never tried before and have learned quite a lot in the process of this build, ill have a few more pics over the weekend, as ive been very busy the last few days and only really did some blending on the streaks, the base is the next thing ill have to do and this will be another first so may be a slow process, thanks again to all who have viewed and helped