They all use the same appliances, doors & windows, luan plywood, TPO roof membrane, etc., etc. It boils down to how well the various factories assemble them. Be aware that "ultralites" use the thinnest, lightest and least substantial components to roll out the factory door.
Look for a brand/model that has a decent cargo carrying capacity of around 2K lbs and up. Options will reduce the CCC and if you load the TT on the heavy side (long trips and/or family) you can end up near or even over the GVWR in some cases.
Avoid the frames that have the I-beams made from 3 pieces of 1/8" steel to look like a "regular" I-beam. These frames flex a lot and can cause all sorts of issues. If you can find one, a TT with a BAL frame would be good.
Besides how well a TT is made, also consider how well the manufacturer provides warranty support. Also research the dealer. A great TT can be turned into a nightmare by a bad dealer. Our dealer was inept and ended up refusing to do warranty work that should have been covered.
If you were on the west coast, an OutdoorsRV/Nash/Arctic Fox would be a good choice. These also have their own in-house built heavy duty frames.
Some owners claim their TT has been problem free while some with the identical unit can have nothing but trouble. Not an easy process to go through but it's great to hear someone inquiring before buying a problem.