69ron; I've done nutmeg oil quite a few times and have found it to be very nice and pleasurable especially in smaller doses, in higher doses it can get quite psychedelic/dissociative. I generally just put it into 00 capsules (a bit under a ml), I'd say start off with 1 capsule which is a nice light dose where you can carry on as you would before, but I have gone up to 4 capsules. This has been tried on two different batches of oil, both with similar effects.
As long as you fill up the capsules carefully to ensure the oil doesn't get on the outside there's no taste and it's a very easy method of ingestion. Oil will leak out over time so I just fill them up at the time of ingestion.
Effects last approximately 12-18 hours, they can be described as very anxiolytic, at times both stimulant and sedative, very mildly dissociative and with a bit of a 'zen' edge to it, with some hints of psychedelia.
Mace oil also works nicely, it's a bit more potent and 'smoother' in it's effects, I'd estimate that it's no more than 2X the potency.
Of course larger doses will give you the nutmeg effects you hear of in trip reports, the highest dose I've done was 4 capsules which was still extremely pleasant, with a whole body 'buzzing', quite a 'rolling' euphoric feeling and some dissociation which could be likened to a small dose of ketamine. Some intricate CEV's were observed with some mild OEV's, and the general psychedelic 'mind opening' and empathogenic effects.
It can cause a bit of diarrhea on an empty stomach, I like to take it half an hour before lunchtime after a normal breakfast, this seems to negate almost all nauseous effects.
The last quote you gave gives a reasonable description of some of the effects too, although with reasonable dosage I find it to be very gentle and overall entirely positive for mental health. I dosed 1 capsule of oil the night before yesterday and the last day has been wonderful; I found myself with a lot more motivation and empathogenic energy and this 'afterglow' of positive energy lasts for a long time after, and I've noticed no comedown or hangover from it. I really do love it and do it ocassionally when I have the time for it 
I'd be interested to try elemi oil though, with the positive ratings compared to nutmeg oil it should be interesting to see how well it works.