Lowmanjason is correct. You have to have confidence in your equipment. BSA may be an ok scope, but will it hold up to your demands? The Aimpoint system is combat proven to be rock solid.
I have seen BSA scopes go tits up by simply falling over while mounted on a weapon. If you only intend it for range shooting, it may be ok. It is not something I want to stake my life on.
If you can afford a good optic, get it. If not, save up for it. By once, cry once is a good motto...