I still have the seat on the bike that it came with. It isn't a very wide seat, but it is a little cushy (gel filled I am guessing). It is made by Avenir. It doesn't appear as wide as some comfort seats I have seen. It felt pretty good up until yesterday when my crotch went numb (mainly towards the front).

I also have had some hand numbness, but I have had this since I started riding (even on the Walmart bike). I wear gloves and the handlebar is padded, maybe I am just gripping to hard (probably out of fear every time a car whizzes past me at a high rate of speed). The numbness in the hands does go away if I wiggle them a lot, but it is still annoying.