When you start to build a platform bed yourself, have you ever thought about the best type of wood you would use for slats? There are lots of houses/building centers that will sell you what they call “pine” but are really spruce/pine. You really should ask for “# 2 southern yellow pine”, which is one of the strongest woods around. So it makes your bed more reliable and it will definitely last much longer.
Another option is to use DF as it is one of the strongest softwoods you can buy – it has a very high modulus of elasticity and is often specified for high load applications in beams and joists. DF is stronger than spruce, larch, southern or yellow pine, and far better than cedar or redwood.