Question about my light

Long-time lurker first time poster. I bought a used thousand watt setup for my 4 by 4 grow tent. First time growing ever. The guy gave me a brand new Apollo bulb and a used digilux bulb with one grow on it both mh. Which one would be better. Digilux said it has 25% better red and orange. Also I'm only running it at 75%

Gosh, it's been years since I've used HID lighting. When I grew with HPS/MH I always leaned towards the Digilux bulbs because of the better spectrum. At the time they were the "overall better bulb" in 2011. Apollo bulbs I believe are categorized in the "cheaper bulb" category.
You may be best suited to try each one out and see if you notice a difference in brightness. Since the Digilux has one grow notched on it's belt it may/may not be as bright as the Apollo.

If they were both brand new out of the box I'd favor the digilux over the Apollo.

if you're using it for both veg and flower, i'd use the apollo for veg, then switch to the Digilux with enhanced red for flower

I have thousand watt hps bulbs for flower. Or should I use a metal highlight for flower. Apollo has a whiter tint to it

didn't know you have a hps bulb.
then i'd go ahead and use the digilux for veg and the hps for flower, save the apollo to use when your digilux burns out, it's not that crucial in veg, the only real difference will be that plants vegged under a bluer/whiter light will stretch more when you flip them than ones vegged under a red enhanced mh