Anyone know much about aftermarket filters?

I've seen Filter packages for Air,Oil & fuel. SAKURA brand - never heard of them but anyone used them?

Can they be trusted? An Air Filter alone costs more than the whole kit.

Run away! That brand is cheap for a reason, they are shite. Quality filters cost far less than a visit to the mechanics or a weekend of skinning knuckles and swearing profusely and having to replace shite filters and any problems they may have caused with decent filters anyway.
Just my 2 cents worth.