Either unit will work fine. The “recievers” MarCum units use are far better than required by the unit to do the job. Also, the power output of the Marcum should be enough to meet any need you will have. But, it is better to have it and not need it than to not have it at all.
Derek’s reference is to a graph similar to the Genetron, they use very low power output to recieve good results. It works a little different in a $400 flasher unit.
If you are getting outfished that bad, it is not the flasher. The LX-3 will be to your benefit if you are fishing deep water, suspended fish, in the weeds and a few other situations. Otherwise both units should do the job.
I am on MarCum’s Pro Staff because I beleive in their products and believe they are the best on the Market. Their engineers know what they are doing and you will be amazed at all the things that have coming out in the near future.
Feel confident in buying that LX-3, you did make the best choice in my opinion.