forgive me for the format, I chose to answer each question individually and numbered .. anyway it's in the order of what you asked.
#1. Well it doesn't have to be the Powercat, that's just the only one I've seen on the market, but make sure you can look at the spike plates as
every sprint spike says 100-400 meters
if you google Superfly you'll notice that
the Zoom Superfly G5 and the Zoom Superfly P2 have the exact same spike plate ... anyway
#2. most Olympic and collegiate athletes I've seen don't wear socks with their spikes, not saying it cannot be done, but if you were wearing socks I'd say go with something very thin, maybe some kind of coolmax variation.
#3. Tight fit, yeah? Has to be, you don't want your spikes too big .. I'd say the fit you want is definitely glovelike. You'd want a tiny bit of toe room, but not too much.
#4. As far as sizing goes, I can' really say too much here as every brand isn't the same, and things can get fuzzy. I went with my normal size and it worked for me so you could do the same. But definitely the sizing is a very big issue when it comes to spikes
regarding actual spike length I think it's 3/8 but if you're buying online it'll most likely say
here's something I found on spikes
http://www.everythingtrac..._3153_A_CategoryID_E_355
**needle spikes I believe are banned on some synthetic tracks .. the ones above are pyramid and come in varying lengths
regarding the dirt issue, you most definitely do not want to be using a track shoe on dirt, let me explain why.
in the sport of Cross Country track spikes (which have a hard plate) can be worn, but considering the different kinds of running surfaces you'd be on, the shoe would be a bit torn up by the surface
**think of it like wearing dress shoes while working construction, yes you could do that, but wouldn't you want something more equip at handling the job?
same would go for wearing a hard plate sprint spike on the dirt terrain. it can be done, but keep in mind hard plates aren't designed for off track surface and would break down much quicker. And since I didn't explain in detail, a hard plate shoe is one with an all, or mostly plastic bottom
a fair amount of track spikes use hard plates .. and before you ask about soft plates, that's explained below, wait for it, lol.
I believe this was already mentioned, but I'll throw that idea out again ... if you're gonna be off roading looking at a soft plate spike might be in your best interest. A soft plate doesn't just have spikes (removable), but on a rubber based bottom it has more versatility
and additionally soft plates usually cost less when compared to hard plate track shoes. You might see the name covered spike come up, which is another name for soft plate. When you're not using the spikes, blanks can be used to cover up the empty plate when you're not using the spikes
hope that helps
