Which turntable is better?

I have both the stealth and the ultradeck. (My third is a Thorens td320 mkiii). The Thorens is my favorite. The Stealth is almost perfect. The Ultradeck is phenomenal.

Thorens has a beautiful resonance and terrific synergy with theTD90 tonearm. You can run any cartridge on it.

The Stealth is a near perfect design and direct drive is so effortless and easy. The tonearm is a little flimsy but I have found you can get the most out of it with a fairly heavy headshell/cart. It has an ink black background which would likely improve with a linear power supply.

The ultradeck is really hefty. It has a huge soundstage. The mofi carts are solid. The 10" tonearm gives it authority. It has audiophile interconnects and a really nice motor. The on/off button is in a bad place and the belt is a little slippery.

Buy a vintage tt before you buy new but if you buy new get the stealth and a really nice cart like a nagaoka mp-300 or 500 (if you listen to rock and jazz).

Rega all day.  Pickup a used P8 on The Music Room if you can swing it. Around $3000 w/cartridge.  Wonderful sound, simple, rugged. 

I own both the Technics 1210 GR and a Music Hall Stealth. Both are positively reviewed by multiple sources. Apart from the ridiculous position of the power outlet and RCA cable connections on the Technics ,the table is quite musical and easy to set up. A true 1200 in terms of weight and torque supplied with the core-less motor. Using the Stealth ,my only complaint is the UV sensitive auto shut down feature. Absolutely useless and should be disabled ( a mere rear switch). Not as robust as the GR however a more nuanced sound IMHO. I never used the supplied cartridge in favor of a Hana and a Nagaoka MP300. Obviously I prefer direct drive. 
 The Technics GR2 can be found  within your price range and is a better table than either the Stealth or GR. A much better choice than the 1500c unless you need a built in phono preamp. Regas are sweet but adjusting the VTA  is a chore. Enjoy the ride. 
  

I have the SL-1500C and have no complaints.  Actually, bought it on and paid $900 and it was in like new condition.  Go on Google Gemini and compare the turntables you are considering.  It will probe the daylights out of you, but will help in your decision. 

Can only comment on the Mofi.  After months of research decided to go with the Mofi Ultradeck with MasterTracker cart and am very glad that I did.  Rock solid, dead quiet with incredible detail and soundstage.  Very happy with the purchase.  Best of luck to you.