Timing Belt Question

I'll try to ask this again, for those who have had their belts done or know about this.

I want to get mine done, and my normal mechanic said he could do the timing belt and water pump, using genuine Hyundai parts, for 800. I know he does good work.

The place i bought the car from said they would order an aftermarket kit that would include the timing belt, water pump, pullys, tensioner, power steering belt, etc.. and they could do all of it for me for 800.

My question is which do you guys think is the better option to go with and are aftermarket parts like this reliable enough to trust under your hood?

Thanks in advance for any responses guys and gals!