I feel you on this
I bought the same thing, however I happen to love this add on. You are very accurate about the batt port and the functionallity of both the RDS and scope. I play SWAT style so the limitations are acceptable for me. I did use this set up in the field and know the frustrations that you have mentioned. If someone plays outdoors then do not buy this set up, indoors this setup works well, for me for me anyways.