I'm partial to getting nic in VG, since I think VG ages better.. No noticeable change at all.
I wrote elsewhere that I had ancient 7 or 8 year old PG & VG (for other uses). I found that the PG tasted and smelled god-awful (and got even more awful after I stopped using it for vape - taking on a truly 'fumy' type smell - just wretched). However, the ancient VG was still perfectly fine. Both were never stored in fridge or freezer.
Another benefit is that in-VG nic will absorb much slower if you get any on your skin... Which might be more of a concern if you were getting 100mg/ml. If you're concerned about the viscosity, just use a syringe without a dispensing tip on it to suck it up. Especially if you got the 100mg/ml stuff, you'll need to draw up very little anyways, at 3/6mg (or otherwise) ending product. ... To make it easier, I use a 4oz wide-mouth canning jar with plastic lid for my 'in-use' nic.
I get my nic from Hartland, VG/PG in four 1-gallon 'gly cubes' from Essential Depot, and flavoring from Hartland, Wizard Labs, and Bull City Flavors. (Bull City Vapor changed their name to Bull City Flavors, presumably in light of the 'intent' clause from the FDA idiots.)
An awesome free calculator is in my sig, but for a beginner, something like EjuiceMeUp might be easier to start out with (albeit quickly becoming a supreme PITA).