Ok so my Witcher experience to date.
Witcher 1 - Never Played.
Witcher 2 - Played a few hours and eventually put it aside.
Witcher 3 - One of the best games i have EVER played.
I was a bit apprehensive getting into the third release in a franchise and not really having much knowledge in the back story. The Witcher 3 does a great job at introducing the newcomer to the rich lore in this series. After some very well written and voice acted conversations I felt at ease with the story, not at all confused by it and left wanting more. Conversations felt fluid and relationships between characters seemed strong and believable.
The main story arc was amazing and really felt like decisions and actions you make along the way have a very real and lasting impact on the world around you. While walking through towns you maybe shunned, ridiculed and spat at by passers by due to the conception of Witchers throughout the continent, however through your actions and decisions you see these actions start to shift as word of your deeds begin making their way between villagers. NPC's can be heard discussing your exploits while adding some exaggerations of their own. Some even giving further information from completed quests in passing conversation.
Secondary quests and exploration is enough to keep you going long after the main story line has been completed. Quests, Contracts, Treasure Hunts and sightseeing. This is the stage im at right now. I am about 60 hours into the game and have many areas left undiscovered and enough secondary quests to keep me busy for a while yet. The detail given to the world around you is incredible and begs to be explored. Ruins, caves and remnants of bygone years litter the landscape, some even offering valuable loot as a reward for getting off the beaten track.
Cannot recommend this game enough! And look forward to further DLC and expansion packs.