Hm.
If your mast/mount is solid and properly dimonsioned (i.e. meets requirements of dish) then the dish should stay in place.
The failing link could be the dish, then. Most metal dishes of about 90cm-100m should withstand most things you throw at them, providing the mount stays true. There are litterally millions of these installed througout Europe that has survived year-on-year.
However, if the mounting position of your dish might mean a high-risk of damage to the dish itself during extreme (but expected) weather conditions, you need to should consider a SMC dish (Channel Master, Prodelin, Cahors/Visiosat etc). These dihes will withstand more battering an abuse by weater and still retain their shape (and performance). They have, however, mostly a higher cost. As for the weight, some of the SMC dishes actually weigh less than similar sized steel dishes, but in most respects there's little difference. Performance-wise, they are very similar to steel dises, and although theoretically equivalent to metal dishes, they do tend to have slightly better gain.
But really; get a 1m dish of your choice, put it up on a proper mount/pole, be happy, and if it goes bonkes after some years - get another one! Don't nit-pick on size, get the largest you possibly can; there's no magic difference between the manufaturers (except for the really sh*tty chinese job). Far more important than, say, LNB make and model. (Not that this is not relevan, it is just minor compare to dish size).
