M10578-A3 has LNA and SAW filter integrated, as shown in the block diagram on p.3 of the data sheet. We have found an additional LNA in most cases may only introduce a small increase in performance, also if the gain is too high it may introduce saturation; the integrated LNA gain is 18dB, if the external LNA is >16dB it will saturate the MTK receiver. For maximum performance, it's better focus on the antenna and good RF layout. We are happy to support you on your design/implementation, it is a standard service we offer to all of our customers free of charge. Please contact firstname.lastname@example.org and let us know which country you are based in, so we can put you in touch with your regional representative.