Finally got around to try the T5. I've been dealing with an allergic reaction (rash/eczema on my palms) to either PG or a specific juice I bought elsewhere, don't know which just yet, and stopped vaping for a week. Now only vaping 100% VG and not using the suspect juice. Still have some eczema but it is definitely healing.
I filled the T5 for the first time last night. I took off the rubber thingy and put a few drops of juice on the coils and down the wicks and put the silicon thingy back on. It filled rather easily with an average glass dropper but one has to be very careful not to go too fast. Slow and easy does it with the T5 tilted at 45 degree angle. I let it sit for a few minutes.
The few initial hits were rather dry with little vapor production. It vaped like this for a good while, maybe 20 puffs or so. Then it started vaping quite well. Nice clouds of vapor and very nice taste. Strangely, for a top coil, the vapor was (and still is) quite cool at 3.9 volts and a coil rated at 2.4 ohm which measured 2.6ohm on my multimeter. Found the sweet spot at 4.4v with nice warm vapor.
After vaping a little more than half the capacity, it started to vape dry again, just like it did initially. This went on for longer this time, about 40 puffs, and suddenly it started to vape good again. After maybe another 40 puffs it did it again, dry, low vapor hits, but never burning, just low vapor production. At this point I thought maybe the juice level was too low so I refilled it. Nope, still low vapor.
I put the T5 down overnight thinking maybe I had a bad unit and would look at it again today. When I picked it up a couple hours ago, it started slow but after maybe 5 puffs it got going even better than before and its been vaping quite well since. Right now, it started gurgling a bit after putting it down for a minute to compare it with a T3. Put the T5 back on and it was gurgling (It stood straight up, never laid on its side so it's overwicking). Took it off the battery and blew juice out and a good drop came out on the napkin, gurgling gone, for now at least. Found a little juice on the battery post so it did leak a little while it gurgled.
Too early for final conclusion as I've only vaped two tankfuls so these are only my initial impressions. It vapes very well when it's going good but seems to have a not very serious overwicking issue. It may take a tankful to break it in properly and it may gurgle from time to time. All in all a very good unit. I still prefer the T3 as I prefer its cooler vapor, its refill ease, and its total lack of leaks. But the T5 is definitely at least worth a try. I will play with it more to see if I can fix the overwicking issue as it works fine otherwise.
Note: Just now it started to gurgle very slightly. I took it up to 4.8v and the gurgling cleared up. Taste still good and warm vapor top notch at 4.8v. So this unit may like slightly higher voltages to keep up with the overwicking. It is vaping up a storm right now. It is almost empty, let me refill it once again and see.... With a full tank it is now vaping thinly, not nearly as bad as before but definitely not as good as when it was almost empty. Some gurgling now, a little leak below, blew a good drop of juice out and voila, it's vaping good again. So yes, definitely an overwicking issue.