1) Yes, a better modeling program makes work flow easier and thus creativity easier and enables you to create better looking models.
2) No, unless you modify something it will look the same.
3)Top 3D applications: All prices in US Dollars
3DS Max - Industry standard.
Price: Max 2008 $3,495[*EDIT PRICE UPDATED, previously incorrect at $1,500]
Max 9 - $3,700
trueSpace - Well known graphics program that is focused mainly on graphic industry but with add-ons exports and saves to game industry formats. Recently the company that makes it(Caligari) was purchased by Microsoft. They also offer many good promotions through email if you download a trial version. They are always having good sales on their products.
Price: v7.5 -$595*
v6.6 - $395*
*Prices can be lower via email promotions
gameSpace - A game oriented version of trueSpace that is void of many of the advanced effects in trueSpace as it provides what is necessary for game design. This version suffers from a non-indepth animation system that most feel a third party plug in ($30USD) is required to easily create animations. Strangely, the calagari main site has de-linked the gameSpace pages from their main site. This might mean that the future of this program is uncertain?
Price: $299*
*Price can be lower via email promotions
Softimage|XSI - Widely used in game industry. Most notable is its free mod tool used for modding half-life2.
Price: $495 and rising sharply up.
Lightwave 3D - Used in the industry and associated with big games such as DoomIII and Burnout 4.
Price: $895 or $995
Upgrade from $495 or $595
ZBrush - Used in the game industry. Lesser known for games.
Price: v3.1 $595
Maya - [UPDATED] Used mostly for the movie industry and non interactive simulations. It does not support almost all of the formats that the game industry uses. It also costs as much if not more than 3DS MAX 9. It is used more by the game industry but not as much as 3DS Max.
[Prices updated:]
Price: Maya 2008 Complete: $1,995
Maya Unlimited 2008 : $4,995
Blender - Used by many people in all sorts of industries. Its free, but its interface is very hard to get used to.
All information that is bracketed is part of an Edit update to correct factual errors in this post. Sorry for the incorrect information.
Think outside the box.
To go on an adventure, one must discard the comforts and safety of the known and trusted.