Time to upgrade the old Dual turntable, looking for opinions.

Check this one out!
http://www.hifigem.com/polytable.html

You can't go wrong with a Rega RP3 or RP6.

There are lots of options in the $1500 range. And it's a good place to be, dollar wise, that is where you jump over beginner tables and get to some real entry level high end tables! 

Shopping used, you've got many options, I paid $1100 for a VPI Scout, and put a Sumiko cartridge on it, and I am very pleased! I have no plans to upgrade any time soon. Perhaps I'll upgrade to a better cartridge one day, but the 'table is great. My son in law has a Music Hall Ikura 'table that sells new for $1200, and he loves it. Then there is the Clearaudio Concept that comes complete, about $2 grand new, but used ones aren't hard to find. I've always liked the Marantz TT-15, a complete outfit that's actually made by Clearaudio with a Clearaudio cartridge on it for $1500 and change new. If you like low mass, the Rega Planier 3 is about $1300, and Sota tables can be had used in this price range too. The first high end 'table I ever heard was a Sota, and it changed my entire outlook on vinyl! so many companies jumping in at this price point with some real high class tables! 

Any one one of these could make you happy, a real step up from the basic stuff in the $500 range. Seems that most folks that start at the $500 range soon upgrade to the next step up, so save yourself the trouble and get something really nice, you will be awestruck at the difference from your old table to one of these new designs. And there are even more names that I haven't mentioned, Funk, Mitchell, Basis, etc.

some folks will preach on the restored greats from the past, and I've no problem with that. Thorens and Garrard, etc. if that's your preference nothing wrong with that. And the Linn tables are also excellent, and have an endless upgrade path! Sorry I couldn't narrow it down more. But I can testify that my Scout is awesome and I have no intention of upgrading any time soon. Happy shopping!

Second the Rega RP 3

So, I’m curious to get some opinions about what modern (or for that matter, vintage) TT’s might be a significant upgrade. Hoping not to exceed $1500 for this, but can stretch a little in the right circumstances

Vintage is fine if your technically inclined!
And while many were built to great quality standards, most of these TT’s are now pushing 40 years old. If you go this route, expect to have to open it up and do some extensive repair or at the very least, intensive cleaning. No matter what the seller says!

Now if you don’t want the fuss that comes with vintage, go new. $1500 and bit higher can buy a lot of great sounding TT’s...

The GEM Dandy Polytable yogiboy recommended is a good one.
So is the VPI Scout Jr.
And finally if you want a vintage look but in a brand new unit built to the same extremely quality standards, then look at the new Technics SL1200GR. It’s 2 grand but will last a lifetime.
http://www.analogplanet.com/content/technics-introduces-appx-2-priced-sl-1200-gr-turntable#8q6cQ0lti...

So here you have three radically different TT’s in design and drive implementation.. Two are built in the USA and the third in Japan so you can be assured quality.
Remember that a great TT is as much a precision machine as it is an electronic component.