Roller Valve Spring vs FT Valve Spring

The main issue is..... the hyd roller lifters are pretty heavy, especially the retrofit style, so it takes more load to keep everything in control.

So, 125/280-ish will work up to some rpm point with a hyd roller cam, but unless the cam profile is rather tame...... there’s a good chance the valvetrain will start to get unhappy at a fairly modest rpm(low-5000’s).
Where it actually happens will be mostly dependent on the cam profile.