Do not sweat for 150MHz.
In case of only the passband thats would be true, but that being LPF, it may be required to attenuate up few GHz range (I dont know the application).
One comment regarding the layout - do no use copper pour on TOP layer, but instead use two individal vias for each grounding point!
But as already mentioned by others, check SRF of Your components because that wil dominate the performance in upper frequencies.