If you shop around, a pair of top quality Lemforder arms will set you back around £200 without the droplinks. Expecting to get a decent pair of arms and droplinks together for £70 is just not realistic. They'll get you an MOT and might be worth fitting if you're going to be trading the car in a few months time, but if you're in it for the long haul, do yourself a favour and spend the extra money so that the job only has to be done once.
There's nothing made that someone else can't make worse, and sell cheaper.