I have both the 370 and the 390Gtx and couldn't be happier with them! The lightness belies the support, sole protection, and traction afforded by these shoes, and to hike in them is a whole 'nother experience compared to heavier, stiffer shoes...about the next best thing to going barefoot I'd say.
Until this summer I always wore Superfeet, but Roger C. talked me out of them. Wow, that really improved the performance of those Inov8s! Without the Superfeet I could "feel" the trail so much better and my foot could flex along its entire length, hence the comparison to being barefoot. Try 'em, your feet will love being liberated!
Another mid-height non Goretex shoe is the Montrail Namche, sadly discontinued, but still availaable at Mountaingear.com for around $49, a steal at that price.