While in a local guitar shop today I was made an offer - trade my 4 string bass for a 5 string and pay the difference in value. I must say, I'm mighty tempted...My current bass is an Indie Swamp 4 and the 5 string in question is an Indie Swamp 5 - same instrument basiclly save for a few details (gold hardware on 5, nicer wood grain on 4).

I'm not sure if I want to trade though. At the moment I'm mostly playing stuff by Coheed and Cambria, Muse, Tool and (strarting to) Opeth - so standard or drop D tuning. On the other hand, I'm looking into playing Dream Theater type stuff which should be easier on/need the 5 right? I like the feel of both basses.

Any advice?
5 string basses are an acquired taste. I personally dislike them but a lot of people swear by them. Not many songs are written/played on 5-strings but if you have a 5 string then you will end up using all the strings when you're writing.
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How would it be transfering 4 string songs to five strings? Just a case of missing the low B I take it, or would it be trickier than you'd think? (Might seem quite a dumb question)
It's simple as. It';s just missing the low B as you out it. Or you do what the low B is there for, and transcribe notes down a string so you can play a bunch more notes in the same hand position. Say you're playing mainly around the 7th fret on the E string. Why go down to the 2nd fret on the E string when you can just drop a finger down a string onto the 7th fret of the B string?
That makes sense...
Thanks for the help I really appreciate it...looking into it however I think I might pass.
I do like the 5 string, but I still love the 4 sting so I would prefer supplement it rather than replace it (and it appears that I could get an Ibanez 5 or 6 string for little more than the cost here, with the benefit of having both instruments).
Still, thank you for your opinions!