mp3 players are compatible with more things and therefore more useful than an iPod which you need to have iTunes for
Um, what? Dude. So many things wrong with this.
An iPod
is an MP3 player. I'm... not sure where you're getting the idea that it isn't.
Compatibility certainly isn't an issue, either; all operating systems have a large amount of iPod management software available if you use the default firmware. More people need to be aware of this:
You do not need iTunes to use an iPod. Most of it is is open-source, too. You're not bound to any type of client at all.Of course, this is all negated once you take
Rockbox into account, which is compatible with any format you could possibly want (and then some) and requires no software.
As for other players? There is some good stuff out there, but Apple's Beloved Music Brick is, sadly, probably the most practical option hardware-wise. It's not
super expensive and will appeal to most audiophiles. (Naturally, audiophiles are going to be disappointed with any kind of portable hardware, but hey.) Bitrate capability, processing power, space - I don't want to sound like an Apple fanboy (because I'm definitely not one) but the iPod really is top-tier here. There is so much more to it than "it plays music," which is why Jetx's post kind of set me off here. Internet Explorer browses the web, you could type a novel with Notepad, or you could edit your photos in MS Paint, but, uh,
why?
Sorry. Didn't mean to sound rambly. Or maybe I did?
Anyway, onto the OP's questions: I can say wholeheartedly with everybody else that you should make space a priority. The speaker has absolutely nothing going for it unless you enjoying hearing your favorite songs sound like a bunch of garbled whale noises. I don't know where you heard that one model is louder than another. It's BS. It may have some kind of effect, but three things will play a much larger role in volume: mastering of the original recordings, encoding, and how powerful your headphones are. The latter two are easily adjustable.
The only thing setting apart different iPod models is space, slight hardware differences, and random garbage add-ons veiled as "features." If you take the Rockbox route (which I
so recommend) space is the only thing that really matters.