Ah yes...the quest for the Holy Grail continues. First it would help to know what type or style of bicycle you have & how far you plan on traveling. Most bikes aren't meant for or designed to travel more than 5 to 10 miles at the most. THE most comfortable type of bike for longer trips is a road bike or possibly even a "touring road bike". I own 2 touring bikes & one straight road bike. ALL THREE have Brooks Leather Saddles on them. Why leather? In those famous words of the late cycling guru Sheldon Brown...
"Leather saddles have only one advantage over plastic, but it is a big one:
1. They are much more comfortable!"
http://sheldonbrown.com/leather.html
Read what's on this link too. http://sheldonbrown.com/saddles.html
Even your question shows (pardon me) lack of knowledge. It's NOT a seat - it's a SADDLE. You sit IN a seat. You sit ON a saddle. W-I-D-E, soft, squishy, gel-filled saddles are NOT the answer. Oh sure...some have a slight amount of gel in them. But most go overboard.
Only your "sit bones" need support. W-I-D-E, soft, squishy saddles do NOT support your sit bones. Padding and/or gel is like water flowing. It will take the path of least resistance. Just as soon as you plant your butt on the saddle, all that padding and/or gel flows AWAY from your sit bones & TO areas of soft tissue & blood vessels - squeezing them off causing MORE PAIN!
Want or need the MOST comfortable piece of leather you'll ever sit on? Get a Brooks Leather Saddle!!! Yeah...they're pricey but worth every penny!
http://www.brooksengland.com/catalogue-and-shop/saddles/
Go to a bike shop & discuss your options with them. Brooks makes a wide range of saddles for lots of different bikes.