Responses from sarah2

TD 124 and Empire 980 tonearm
I have a 98 arm (980 is the same except for the headshell) om my TD124. I've been using a Denon DL-103R for the past year. It's a heavy arm so you need a lowish complaint cartridge. Sounds amazing. Try a Denon DL-110 also, no kidding, it's super f... 
Empire 208 turntable
Herbie has a mat for the 208 and you don't have to mess around with the 45rpm adapter area. Heard no difference lifting the motor cover. 
Empire 208 turntable
Yes, it's worth it and the arm (model 98) is better than most think. The Denon 103 & 103R sound really good on this heavy arm. Key here, heavy arm for the Denons. You really can't get away with elliptical stylus or finer because of the set geo... 
Thorens 124 spindle bearing.
Have you pulled the spindled and looked at the ball bearing? 
Supex 900 question
I'm pushing 2.25 grams and it tracks through 6 & 7 fine but not 8. The warmth and smoothness of this cartridge is very seductive, not muddy. Very balanced sounding. You have to load it @ 40ohms at least with 15 to 20ohms being best. SUT loadin... 
Denon 103 or 103R, Matching/Specs. w/Rega Arms etc
The Rega will work but you won't realise the real potential of the 103 on that light of arm. Yeah it's a lot of work. This is an education process that I believe you can not just look at. Plan on spending a lot of time here on Audiogon, Audio Asyl... 
The Truth of the Philips SACD1000
What does the rest of your system consist of? I've read on AA that the SACD1000 takes up to 300 hours to break-in.