Compare Speed and MAP of ssd_efficientnet and ssd_mobilenetv2

[PythonImageDeveloper]

Hi @CasiaFan
In your opinion:
Q1: The ssd_efficientnet in terms of speed and map is better ssd_mobilenetv2? Did you test?
Q2: What's difference between ssd_efficientnet and ssd_eficientnet_fpn? I thought the ssd networks that use the fpn are similar to yolov3, right? In the FPN network is use up-sampling layers, right?
Q3: Is it possible to use just only three layers for detection head instead of 6 layers?If so, How?

[mashrurmorshed]

I would also like to know the speed and mAP comparison if possible : )