Wow, I love classic naked bikes! I've been quite motivated to by a GS1000E once and did buy a 1978 GS550E, but to be honest, I would avoid the early 80's Suzuki's. While the GS engines are absolutely bullet proof (amazing engines) the electronics, wiring, relay's, etc that Suzuki used in that era were a HORROR story.
My GS550E was $350 and the GS1000E I was looking at was $1100. (back in 2002 though). That would make them a 20+ years old, but now, we are talking 30+ years old... As much as I love the 80's UMJ, I wouldn't give up a 2006 bike for one.
Have you considered a newer UMJ like the Bandit 1250 or 1200? (same engine as used in the GS1100 just upgraded), or FZ1 or the ZRX1100/ZRX1200 or even a CB900F or CB919?
Actually, you might find this really enjoying of a read as I talk about a lot of the old bikes here:
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