I had a H&R Topper, the 158 earlier version in the late '70's.
It ate brass, wasn't satisfactorily accurate, so it went away.
Some report good results with the Pardners. I too had a Handi rifle in .243 and .22mag. The .22mag was ok, but I traded it for a Rem.597 .22wmr auto. The .243 was like the previous mentioned .22-250. Shot patterns, not groups.
I think you'll like the one you got. With a 1/9" twist, it'll handle most any .22" bullet. The newer ones will take and hold a trigger job. The '70's version had poor metal in the trigger and pull got bad after ~300shots.
To match the .22mag is really easy, and will save $$$.
My favorite powder for this is #2400. I use a 50gr cast bullet over 6.2gr of #2400 for ~2,000fps. It does everything the .22wmr will and most anything you'll use a Hornet for.
My other go-to loads for the Hornet are a 40gr Sierra Varminter HP (you can substitute a blitz king or Nosler BT) over 12.5gr of Hod.Lil'Gun (accuracy load, not hot, but still FAST!). This is my go-to load for deer with the Hornet (shot placement x3).
Also, 33gr or 35gr V-max over 8.3gr #2400 for 2,300fps (extremely accurate), or 11.8gr of H110/Win296 for 3,100 fps.
Don't over scope the Hornet. A 3x-9x w/adl. obj 32mm is just right. Keep it light and Handi...
Get the Lee deluxe die set w/collet neck sizer. Also a Lee universal neck expander. The Hornet brass is very thin and expanding slightly even for jacketed helps. Lastly, get a Lee factory crimp die. Crimp lightly after seating even bullets w/o cannulure.
Welcome to the Hornet club. You'll never be without one again. BTW, I had a K-hornet. It wasn't a happy experience. Another story for another day...