Hi Thierry,

I own a Pair of G3's but never owned a Pair of the Guide Models but do know that the only difference is that the G3's has an increased puncture and abrasion protection, and 20% more breathable
Added protection on leg and seat, Gravel Guards,Fleece Hand Warmer Pocket,Flip-out Tippet Tender pocket and a different Color at the Knees.But they are very Comfortable Waders.You can get them on Ebay for good Prices sometimes.