Idk if there's a certified "best client for follower count", but from my experience the Amethyst counter is useless, nostr:npub12vkcxr0luzwp8e673v29eqjhrr7p9vqq8asav85swaepclllj09sylpugg is much better. It also orders the list by followers when you pull up the tab to see who follows you, which is awesome