Let's talk hair.
I'm not high maintenance when it comes to hair. Mine is mostly brown and tied up in a ponytail. It's not perfectly straight but it's not curly. Just a little wave here and there. I get a trim when I start to see split ends or if I want a little more shape but otherwise, it's styled in some variant of long and layered. I don't color but my hair does get dry. For special occasions, I like to leave my hair down so I bring in the masque of shine.
For years I've used the Kerastase Chroma Reflect Masque. I know this is for color-treated hair but I've found that there's no reason I can't use it even if I don't color. If anything, I think that means it will be nice and gentle to the hair. I've been hitting the pool a lot lately so I've been using it every week and I still love it. The instructions say to towel-dry hair before application but I usually just wring my hair dry with my hands and massage it all over. I leave it on for 5 minutes and rinse. I let my hair air-dry (very rarely use a blowdryer) and go to bed. The next day, I get a beautiful shine. I've also noticed a lightness to the hair, which I sense even as I'm rinsing the product off. It's fragranced but I find that it doesn't linger and it doesn't bother me. All I notice is that the hair is soft and shiny.
Once, after a recent trim (and my hair was around shoulder-length), I used it and then slept in wet hair. I got complete flatness the next day. It's happened only once and I suspect that maybe I just left it on too long or didn't rinse it out as well as I should have. I asked Aleya (who writes for the Hair Design Institute, a beauty hair school with locations in New York and Florida) why hair could get flat after using a masque. I was told that the masque and/or treatment could be too heavy for the type of hair one has and that the hair needs protein for body. If that's what happens with you and your hair masque, the advice given was to get a more lightweight moisturizer for the hair and a protein treatment as well. As for me, I think I should stop sleeping with wet hair.
Overall, Kerastase Chroma Reflect is still my favorite masque and I've tried a few. My last disastrous experiment was with the Ojon Restorative Hair Treatment which had an odor I didn't particularly like (somewhat smoky, kind of incense-smelling, and lingers) and did not seem to have much of a positive effect on my hair. I've tried the less expensive L'Oreal hair masques too. I bought one at a Sally Beauty once but so far, nothing beats Kerastase for instant gratification.