I was not sure wether this post was appropriate here but anywho:

I have owned a pair of magnum classic boots before and used them for general use around the barracks (marching and day 2 day wear) I was thinking of buying another pair is this a wise choice? because I don't want to buy £50 ($80) worth of boot if it isn't a good move

Thanks guys =)

All depends on your unit's policies on non-issued footwear, and if they were comfortable for you.