Well I was skeptical at first because my hair is very oily and I wash it every day as a result, but I finally bit the bullet and did a conditioner only wash today. I wasn't planning on leaving the house anyway. LOL! :D

So far I love it! My hair is definitely softer and it's not tangling nearly as much. And it seems to be hanging straighter if that's possible. It is a bit limp and heavy at the roots. Is that normal?

Mostly I just want to know what to expect. With straight, fine, oily-prone hair, how often should I do CO, or should I alternate between CO and shampoo/conditioner... :-? And what's a good conditioner for my hair type? At the moment I'm using Pantene Pro-V Volumizing.

Glad your experience was a gppd pne!  It's only one time so what to expect is up for grabs.  I'd CO a few times before any conclusions are made.  See if your hair likes it and if so....continue!  If not,you could try another conditioner or wash and condish or include a ACV rinse to get rid of any build up.  Only time will tell.  
The conditioner you are usins sounds like your hair likes it,so why fix it if it's not broken?!  I believe a few other members also use Pantene and it works well for them.  I'm sure others will offer comments(hint) ;)

Straight, fine, oily...sounds very familiar. ::)

Usually, I do CWC's. But when pressed for time or when I'm going in for a trim, I'll do a CO. Suave Naturals conditioners are great. Very light, pleasantly scented and oil-free. :)

As for what to expect: greasy roots within a few hours and parched, tangled ends. Be sure to use a leave-in on the length and something to coat the ends so they don't tangle. HTH

Thanks guys! :) I do use Paul Mitchell Skinny Serum to protect my hair during blow drying. And I think it may double as a conditioner... I know that it leaves my hair softer, shinier, and less tangled.

Thanks for the suggestions! I'll try a CWC next time. Maybe alternate back and forth as needed.