I can only answer for my experience with Thermage. Antilax, a mixed technology of Radio frequency and infrared light developed in Korea, is not available in the U.S. There is very limited information on this company and limited display of any patient results.
Thermage, done right, is not painless. To effectively tighten the skin, substantial temperature increases must be reached to both recoil existing collagen and start the process of new collagen formation.
Heat hurts and most patients will attest to the fact that Thermage is not a painfree procedure. If it is, then chances are slight that you would see enough tightening to make much difference.
Unfortunately the marketing of effective technology tries to minimize any downtime or discomfort. But in reality, most truly effective technology, from Thermage to Fraxel Repair to laser hair removal, involves different levels of pain or discomfort. All patients have varied levels of pain tolerance so all patients experience a different threshold of pain.
Expect Thermage to have subtle firming effects. Some patients get the "wow" factor, but most do not, so set your expectations accordingly. Obviously Thermage has enough effect as it is still quite popular both here in the U.S. and abroad.