Elk two-way sensor battery life issues

We are a dealer and generally avoid wireless unless there is no other option.

We have consistent issues with battery life related to Elk two-way sensors. My understanding is that the further a sensor is from the gateway, the harder (or more frequent) it must work to communicate thus the battery drains faster. The issue is that we have sensors near gateways that seem to not last more than a couple of months before reporting a low battery condition. It has become such a consistent issue that we have stopped using these altogether and instead use 319.5 sensors.

We have every imaginable scenario…

1. Gateway’s in closets, out in the open, in walls behind keypads, in mechanical rooms, in crawl spaces, in attics, etc… our options are never perfect and often limited. No client wants to see them out in the open.
2. We rarely get more than a year out of a fresh battery (especially the 6021) and sometimes not more than a week.
3. Walk tests of sensors indicating between 4 and 8 are sometimes worse performers than those at the cusp of the range.
4. Connection range and battery life is often sketchy after 30ft (open air).
5. On one job it is especially bad, I have a small room with a gateway and approx 6 sensors. The batteries do not last more than 2 months. My thought is that the sensors may be trying to communicate with a gateway further away. I am not sure if there is a way to test a particular gateway unless we disconnect all of the other gateways first?

In many cases we have added more gateways but this has only improved a couple of scenarios. I do not have a great sense of how multiple gateways may help or hurt a network of RF sensors.

Does anyone else have similar problems?