I haven't had any problems with coils since I started soaking my coils as @mikepetro suggested. I only soak 1 at a time usually for 2 days. Once I feel my coil starting to drop off, I drop a new one in PG or VG. I only use one DIY juice in the penguin. I've used about 250 mL so far in the penguin. Its a strawberry, acai, coconut that i mix at 8%. I think it's fine for flavor, but if I want to enjoy a rich bakery flavor or something multilayered, I use an RDA.