Badminton Training Racquet place in improvement

Hello all
I have been successfully using light headed racquets for years now for my regular MD games. (Head heavy/stiff racquets give me elbow/shoulder pain)
A few days back i misplaced my kit bag & i was left with my Carbonex 21special (2U) in the closet that i use for wall practice. The opponents weren’t particularly strong so I started playing with the Carbonex.
As the games continued i was surprised at the relative ease i was able to play most shots with the heavier/stiffer racquet, even when the tempo got faster.
That got me thinking about actual Badminton Training Racquets that weighs above 100gms.
I usually use grippers, pull-ups, bo staff exercises to train my fingers/wrist/forearms.
Do you think that an actual training racquet supersedes the aforementioned routine?
As i see it :- An APAC training racquet is relatively cheap and should be a one time investment.
But if it’s just about overloading the small muscles then I’m doing that already !
What’s your opinion on investing in such equipment?
Please note that im only willing to invest if it will match the benefits of other exercises that i usually do in my spare time to up my arm strength/endurance.
I don’t play other heavy racquet sports.
Thanks.