I had the SG35 as my first guitar. It didn't happen in 1973, so it must have been collecting dust in the shop for a while?
- Good: It has an actual mahogny neck and a rosewood fingerboard. Considered good things today. It's lightweight. Playability was good - after all I learned to play on this thing, and today I am a professional guitar teacher!
- Not so good: we are far away from SG2000 (Santana's model). Tuners are not that good, nut is poor plastic which cracked. Humbuckers were ok, but it sounded kind of 'sour' - don't know how to decribe it better. Bridge had plastic(!) riders, and those kills sustain and are also prone to breaking. Tail-piece a very simple piece of bent metal. Electronics worked as they should - I never had contact issues. Pickguard looks actually quite cheap in near sight. Never liked that feature. I didn't like the burgundy colour (a only available - but is there any 15 year old that likes that colour?), so I sanded it down for a DIY paint job. I then revealed that the body is made by several/many pieces of light wood glued together, with veneer on top. No wonder sustain wasn't that great. We are FAR from an SG2000, yes...
However with today's retro hysteria prevalent, I somehow regret that paint job (silver spray failed, white applied with a paint brush was ok). When I look at it today, the whole guitar actually has a great punk aesthetic. Should have kept it - would have given me a lot of cred today
Eventually I took it appart entirely to experiment with the parts and pickups for some avant garde things.
I see my exact model for sale at Reverb for around 600 USD. That's insane. Perhaps ok for collectors only. For sounds and playability, the SG35 is not a 'hidden treasure' in any way - in my opinion! But it was an okay beginner's guitar, and worth it's value back then.