One con though, it does seem to hurt reception

I've always had a not so stellar reception in my area as i'm kind of covered by some hills

so it might just have bad reception on S4s.

As far as asu numbers, a higher number indicates better reception, so 27 asu is better than 24 asu

the huge battery covers the antenae or something because It also seems to weaken the reception of signal with my coverage going into "extended" in the interior of my house

As far as asu numbers, a higher number indicates better reception, so 27 asu is better than 24 asu

no doubt an impressive battery but has a flaw in design, it covers the antenna reducing signal, this may not be an issue to some but for people like me who are always surrounded by concrete or constantly in regions with weak reception, the battery blocks signal completely.

good battery but u will get bad signal reception because the battery cover the antenna in the phone

I live in an area of bad reception anyway

Despite my concerns mentioned above, I'd still highly recommend this battery if you live in an area with moderate to good reception