Tru-oil is a great (if time/labour intensive) finish for guitar necks. The trick is to do lots and lots of very thin layers.
I finished the neck on my tele with tru-oil:
I think I ended up with 15 coats in the end? It's been more than two years and it still great. Very smooth in the hand and fret board still looks fine.
The "technique" I found looking online was to apply the oil with my finger. I'd literally just dip my finger in a bit of tru-oil and start rubbing it onto the neck, starting at the top and moving slowly down, section by section. I'd rub the oil until I can't get it any thinner and then re-dip my finger and continue (when the oil starts to feel warm from friction I would typically move on).
You really want to get it as thin as is humanly possible, to get as even a coat as possible and avoid any runs/teardrops from forming. The only tricky section where the oils wants to pool is on the fretboard next to the frets. I used little squares of drip coffee filters to rub against the squares after I applied the oil to remove the little pools of oil.
You can do probably max two coats per day (morning/evening). In between coats lightly sand with 0000 steel wool to knock down any dust/other high spots that might have settled while the neck cures. After you've applied your last coat you want to give the neck at least two weeks to fully cure. Remember when I said time intensive?
Once it's all cured you polish up per normal. You can go through the normal grits and liquid polishes for a glossy finish or simply hit it up with 0000 steel wool and then some denim for a matt/silky smooth finish. I went gloss and it's held up remarkable well. Glossy is not as smooth under hand as the matt (it's not sticky though as new nitro finishes tend to be), but it does become smoother with use.
Have a google, look particularly on TDPRI, as there are lost of threads online about tru-oil tips and tricks.
So yeah, it's not the easiest/quickest finish to apply, but it has the advantage of just needing your finger, a coffee filter and some time.
Properly applied (taking it slow with lots and lots and lots of layers) it looks damned good though.
