Around what bhp levels do ya think one would need an upgraded fuel pump.

The pump in my 280 is stock, replaced a few months ago.
Under cold weather, and 17psi my car leans out quickly and randomly. I've been thinking about upgrading the pump, and seeing if that would help out.

I already have 2 450cc injectors, and those should be enuf to get me ~300whp before needing more.