I was surprised how well this unit does when on straight roads. Has nice line of sight range but suffers when the terrain has hills and or curves.
Overall I am impressed with this $45.00 detector. If your budget is under $50 then go for it. You may even be able to get the SRT-35R which is the step up to the SRT-30R.
A great price and adequate range at reasonable speeds to achieve PSL.