I pushed Mullaghanish 4h 30m tempo from TR to my Garmin and they are very different.
Out door description on TR
Power Based
Warm Up:
- Ride for 5 minutes gradually raising your power from 98 to 134 watts.
Main Set:
Settle in for 260 minutes between 134 and 181 watts.
Cool Down: - Spin easy for 5 minutes.
Garmin version is VERY different. The floor is the same, but the top is 30w lower