OK, I now have both a Silver Defender and a Silver iStick 30W.
I prefer the Defender, though it cost me $45, while the iStick was $33.
They have very similar electronics, same chip type. The iStick 30W
is more modern in that it has the Lock feature that the Defender lacks.
The Defender tops out at 25 watts, the iStick 30W at 30. But the
Defender is a little bigger and heavier, the battery is (?) 2600 mAh
rather than the iStick's 2200 mAh. The iStick now looks better with a
full size tank, as there's a lip that makes it look OK on the edge. The
Defender positions the connector dead center, I like that better. The
nice thing about the Defender's connector, other than being spring &
solid stainless, is that it flips over to reveal an eGo connector, so you
don't need to carry or install an adapter. Apparently both are good
in pass-through mode, and both use a micro USB connector to
charge from. The feel in the hand of the iStick is a bit light, it has that
Bic lighter thing. The Defender feels more substantial. The finish on the
two is very similar, the iStick have a finer-grained crinkle. The Defender
has survived for over a week of constant use, the finish is solid. I love
the Lanyard on the Defender, as I tend to drop off to sleep late in front
of the monitor sometimes, and drop my vape. Boing. The lanyard rules.
Both put out non-chopped flat DC when powering a load. I haven't
studied either under varying loads, but I did notice chop on the iStick
when the load was removed. I can't vouch yet for the accuracy of
the displayed voltage/power on either device, but I wouldn't expect
much. It's just a figure o' speech ;-) I'm not sure the iStick is really
much closer to 30 watts than the Defender. I don't care enough to
actually test them.
As more of the Defenders arrive, I would expect the two to be very
similarly priced. The iStick has the lock on the buttons, and 30 watts,
the Defender has the lanyard, the reversible 510/eGo connector and
a bigger battery at 25 watts tops.
The iStick is truly tiny, looks better with some atomizers, worse with
others, personal call. The Defender has a more solid ring, and with
today's massive RTAs, hosts them better IMHO, that offset looks
sillier as the RTA gets bigger. Of course who cares about appearance?