Manic Panic is WAY better than Splat since it doesn't bleed in the shower half as much. I swear I dyed my hair blue with Splat and a week later I had a blueberry colored bathtub. Manic Panic does bleed and fade but not as bad and not as fast. As far as I know it only comes in that gel-like form. I would suggest bleaching your hair at least a little because you'll get a weird effect if you have dark hair... even with the darker dye colors. Don't get it form Hot Topic though. THose are always sitting there for way longer and they curdle and harden and don't have as good of quality (I dont care what the bottle says about being able to keep it stored for a long time) Get it from a pharmacy or a beauty supply store like Sally's. They restock quicker and you're more likely to get a batch that hasn't been sitting there collecting dust and congealing.
I've used this before, and I have dark brown hair. FYI I was using purple.
It didn't last too long - about two or three months, although it was during the summer and I had to wash my hair a lot so that probably had an impact on the time. My hair stylist tells me that the dye will last a lot longer if you wash your hair with cold water if you can stand that.
The color was very nice, though. Despite being a weird color it looked pretty smooth, unlike a lot of at-home color products I've seen.
I don't think Manic Panic is available in my country, but I use Fudge Paintbox with excellent results (it's my first time using a bright dye, so I don't know how long it will stay blue). I bleached it before adding the colour. And it might not last in your hair, as it depends on the condition of it. I've been told that washing in cool water is a good idea to stop colour from running.
The dye I used was really easy to use, more so than any other hair dye I've ever used. Good luck!
It's different for each person. The only way to know is to try it. Those dyes are really picky.
If you don't bleach/dye your hair, it's probably going to last 1-3 months, probably on the lower side if your hair is dark (it may not all wash out, but it will fade to the point you can't see it).
Same goes for what works for you. It depends on your natural hair and how much processing you do on it. For me, Manic Panic doesn't last very long and washes out unevenly every time I've tried it. Splat color fades really fast and never fades out completely, I use it for pink and nothing else. Kool Aid works fine in my hair, too, though the color is harder to keep even and it also never fully washes out.
Special FX has almost always worked really well, and I prefer that brand. I only had trouble with the dye one time, and it was a color I'd used before and since, apparently there was an issue with that particular batch.
I'm using Directions, but I was told that it's the same as Manic Panic and yes, it's a gel. But if you have dark hair you should bleach them before using the hair dye or you won't see a lot of change. Also the colours stay longer on bleached hair. I normally dye my hair one or twice a week, it depends on the colour.