I'm having no problem printing ABS on mine (I have the Alpine ATX PSU), I checked my ambient temperature this morning and it's around 15°C with the room heating turned off and the bed does make it to a reported 100 (I have the new firmware with updated thermistor betas, so this reported temperature is likely to be near the truth, I'll be getting an IR thermometer later for peace of mind though). I've turned on the room heating to see if the downdraft makes prints curl, and if the higher ambient temperature stresses the PSU (currently at 21°C and no issues, it's still printing ABS happily).
Ray