Spare bass

So I got a Yamaha RBX375 for $70 today and I've been wanting another 5 string for a while so I could detune. But then I got to thinking about flats on a bass too. So what do you guys think, should I get flatwound strings on this spare bass or should I go use this bass as a lower tuned one? (probably tuned ADGCF)

Depends. Flats for metal don't sound as good as rounds. I'd say only put the flats on if you want to play stuff like reggae, jazz or soul. Soul sounds really nice with both rounds and flats, actually.

May I remind you guys that Steve Harris uses flats

Though, I would still suggest downtuning it. Putting flats on a spare 5 string for the sake of it is too expensive.

How are flats more expensive? The prices seem exactly the same. As for downtuning, I'm worried about not having big enough gauge strings (I like my strings pretty tight) because I doubt this bass can go above a .135 just like my other bass can't.

They're more expensive over here. Rounds are generally about £20-£30, flats can exceed £40. (for 5-string sets)

Well I payed $35 for my 5 string rounds on my EDB, so there isn't much of a difference.

Wow what? My Ernie Ball Hybrid Slinkies cost me about £10.

The B string is usually another £7 - £10

Plus they were heavies. I don't know if that had anything to do with it. But yeah, so do you guys think I should risk having floppy strings and then having to get a set up, or just get rounds? I'm seriously 50/50 on this.

Well it's a spare bass, so I'd experiment. I'd pick the cheaper option and if it turns out that that ain't mah styyyyle, I'd pick the other option.

Good answer. I'll go with the flats then for now.

Anyone have any particularly favorite brands for flatwounds?

My D'addario Chromes were pretty nice. I don't know any other flatwound string brands

I second the Chromes. I have them on my 5 string and they work wonders! They are supposedly a bit sharper than the avrage flatwound set, but I haven't tried any other so I can't confirm it.
Sharper as in having a brighter tone...not that you'll cut your finger on them. Oh...and the best thing about flats - sliding! It's never been more fun!