@pstevens Of course; but perhaps I should add a disclaimer that if you're going for kettlebells ONLY, I would always recommend going heavier as I do.
24kg is fine depending on your body weight and if you're doing other exercises (such as body weight work), but to do such light weight as your sole training wouldn't yield as great results - then again I have never done super high rep workouts because I'm lazy. I can imagine upwards of 100+ rep sets of lighter weight would be great.
I also outgrew 20kg swings quickly and immediately went heavier because of aforementioned laziness. I'm now swinging 64kg easily (ordering heavier tonight), cleaning 48kg and doing front squats with two 24kg. I will never need to go heavier on anything at this point, just increase reps (front squats with 48kg + 24kg is the next goal).
My physique changes: great butt, monster traps, THICK back, incredible grip, bigger forearms and good hamstrings. This is all from swings alone.
Other changes/perks: cardiovascular endurance has improved without ever stepping on a treadmill. My legs feel 'hungry'; I feel like I can run forever. Train at home. Everyday. Whenever I like. And here's the big one: BANG FOR YOUR BUCK. No single training tool will make you a more well rounded athlete than kettlebells alone. Cardiovacular endurance, strength, POWER, mobility, explosiveness, heart and lung capacity, etc.
I think of it like this; would you be more scared of/impressed by someone who can deadlift 500lb once, or someone who can smash out 60+ reps of 60kg swings of sheer explosive power. It all depends on goals, but I'd much rather be the powerhouse workhorse than someone who can do the former. It's much more practical.. Again pertaining to what your goals are..
For reference, I'm 5'11 and about 200lb after a ballsy Christmas break. Soon my tools will be: 74kg kettlebell (swings), 48kg kettlebell (cleans) and 2x24kg. I will never need to go heavier in my life. I will eventually just focus on increasing reps with these tools.
Sorry for the essay. I love talking about my bells!