I am getting ready to build a spinning rod and I have been considering using the Fuji hooded reel seat. My concern is that I may lose too much sensitivity. The way the foregrip covers the reel foot makes me think it will act like an insulator. Does anyone have any expierience or comments in regards to this style of reel seat?

I have used factory rods with that type reel seat and have not noticed any problems, but. . . those rods themselves were not top of the line rods.  I think that the more sensitive the blank, the more important it is to have the rest of the rod designed for max sensitivity.  I think you can dull a great rod with the wrong components, and reel seat would have to be one of the most important.  Having said that, the foot of the reel is still going to be in contact with both the rod and your hand, so I doubt if it will dampen sensitivity noticeably.

I use woven graphite reel seats on my rod builds.  I use masking tape to build the rod blank to the proper diameter.  Then epoxy the seat to the rod, which should give a direct path for "feel."  People using the rods rave about the sensitivity of the top of the line rods, so I think it does a good job.  I expect they are also lighter than the type you mention, but am not sure.  Light weight is a very high priority with me.

The reel seats cost about $10.00, which is sort of high for reel seats, but I like to use high quality components.  They really grip the reels well.

One issue I havn't figured out yet is that the reel seats are 4 inches long, which is longer than necessary for my spinning reels.  On my next build I think I will shorten the seat about 1/2-3/4 of an inch in order to shorten the butt section of the rod a bit.  They seem a little long, sometimes causing the butt end of rod (with 9 inch rear cork-may shorten that to about 8 inches, too)  to hang up on my biceps when jigging while seated in a boat.  Anyone with comments about this issue?

Thanks for all of the info. I agree with you about the trend towards excessively long rod butt sections, they are not designed for fishing out of small boats. I had an old Lew's Speedstick with a pistol grip and it was may favorite worming rod until it got stepped on.