Version 1.6.1 was a major update that added features like the updated NW.js for better performance. If you purchase or trial the software now, you will automatically receive the most stable and up-to-date version (which may be 1.6.2 or 1.6.3 depending on the platform).
RPG Maker MV is frequently on sale for a significant discount (often 80-90% off) on Steam . You can add it to your wishlist to get notified when the price drops. RPG Maker MV 1.61 Free Download
This software is occasionally featured in Humble Bundle deals, where you can get it and many DLC packs for a fraction of the retail price while supporting charity. Version 1