I'm in the market for an upgrade on my guitar. I've been playing for about 3 years+. Umm my budget is around $300-$400 i could probably get up to around 500.
Would it be better to just buy a used better guitar or a new guitar in my price range? New I was looking at the Seagull S6 but I don't know what I would get used any recommendations/ Ideas.

I smile because I have no idea whats goin on
I'd get a new one unless the price of the used is really good for the quality
Epiphone G-400 Ebony
Line-6 UberMetal, EchoPark
Boss RC-2 Loop Station
Traynor YCV50Blue, Bass Mate 25, Guitar Mate 15
Just try everything, personally I would get a used one because I don't mind cosmetic blemishes all that much. Some really really good stuff can be had $500, personally I got my Guild Jf55 for $850 so you'd be suprised at how much bang for your buck you can get with used stuff.
^^ I second the Masterbilt if you're looking at new. I saw one for $400 new at Guitar Center last week. It think it was for the demo, but still... if I had the cash I would have snatched it up.

If you're looking at the used market you'll have to be a bit more patient but like Siren said, if you look carefully you're bound to find a real gem for a great price. It just takes more time and effort if you're shopping the private market. Meeting sellers to test guitars can be time consuming and you're likely to be disappointed many times over before you find the one for you.
just do your homework on a used piece...i bought one about a month ago and didnt really look at it...once getting it home i noticed a wave in the soundboard, turns out it was not humidified and was dry...then i did more research and found out it was a factory second blemish model....so i ended up returning it and bought new...just make sure u check it out first
ESP Eclipse with blackouts (Snow White)
Taylor 814ce (tabacco sunburst)
Dean Dime o Flage
Spider valve mkii
Fender Super Reverb
Peavey Vypyr 15