I rate them pretty highly (along with Darkstar Vapour in York), getting 15% off my order every time from both doesn't hurt either
I've got one that I use daily (thug juice) and a few others that I'll stick in different tanks/drippers. It's to a point where I've just ordered 250ml of the thug juice in my preferred config which is plenty for about 4 months or so sub-ohming and am looking at buying the concentrates so I can make it myself as and when needed. I usually stick to Hazelnut spread (almost a tobacco style nutty flavour), Faux Hawk (menthol and sour fruit) and a few of the fruit menthols (blue/black/red ice, orange ice is rank!), moo juice (strawberry milkshake) is one I usually use in drippers as it's got a rich creamy flavour.
Hazelnut spread is in my Goblin Mini at the minute on a single coil 1.1 ohm twisted build, lower power suits the liquid nicely, Blue Moo is in a Kayfun Mega clone on a 0.16 ohm nickel build and a 0.3 ohm dual twisted (soon to be clapton when I get round to making the stuff!) build on a Velocity RDA. The thug juice is in a couple of Kanger Subtanks in either RBA mode or nickel temp coil and work nicely in a 60pg 40vg mix, has some wicking issues any higher on the old RBA deck but got a couple of the new ones to try out
Sore throat and ulcers is usually PG or additives. It can also sometimes be down to the vaping carrier (cotton, silica etc) as silica always used to make my throat hurt after a while and higher voltages/wattages/temps exacerbated this. Drinking a lot of water too seems to help
Make sure the juices are well steeped (not really steeping them but it's the term for it) and out of light and the harshness usually goes away, only downside is anything menthol can go funky when the crystals lose their strength.
They do a 5x <size>ml tester mix where you set the strength and pg/vg and choose 5 bottles from the standard range. Darkstar do the same but only in 10ml (don't think you can change the pg/vg either from them)
Discount codes are on
http://www.planetofthevapes.co.uk/discount-codes and it's worth checking out, as is checking what CHV have as best sellers for MBV liquid, they are usually a safe bet and if you're lucky you might get a few freebies to try other flavours