http://www.fuzzylogicequine.com/

 These are so stylish and comfortable that I own a second pair to go shopping in.  I have gotten compliments and surprised looks when I say they are riding pants.

 That 2" elastic waistband does NOT roll, no matter what you're doing.

 The summer weights are plenty warm for me in the winter but I'm the person that keeps the house at 62 because my internal thermostat doesn't need it to be any warmer.

Cool!  Thanks!!  I will check them out.

 Those look really good.  I may have to get some. 

It's really all personal preference.  You don't HAVE to ride in fullseats for dressage.  I hate them with a passion and will not ride in them.  My favorites are Kerrits and Irideon.  Devon Aire makes nice stuff that won't empty your wallet.  Go to the tack store and try on everything and get what's comfortable for you. 

www.tackoftheday.com

They have a new item everyday at noon (except weekends) and sometimes have some awesome deals... 

 Agreed -- you do NOT have to have full seats for dressage.  I find they are generally a waste of money and make no difference to me so the majority of my breeches are knee patch.  Buy what is comfortable for YOU.  Devon Aire, Riding Sport and TuffRider all make comfortable, affordable breeches that I like.

I don't know if the fullseats just don't fit me right or what but I never feel like I'm sitting "in" my horse with them on.  I always feel like I'm sitting "on" him.

 While full seats are "proper" for dressage, knee ptach breeches are not improper. Wear what feel most comforable to you. If they make you uncomfortable, it will affect your riding!

 I really like TS breeches, but don't really like the price, so I only buy them on sale, lol. They are the best in the hot sticky summer that seems to last 10 months (or more) here in Houston. (Just FYI, today's high is 78!)

However, as a very short-waisted rider, I have to say that you must first find out which brands fit you and which don't. While Devonaire breeches may be perfect for someone else, I prefer to have my waistband NOT touching my bra. Even Ariats are a bit high waisted on me (I only even had fleece tights from them).

Go to a local tack store - hopefully one that has several different brands. Try on lots (even after you found a good one), and take notes on how the different brands (or even different lines from the same brand) fit. Pick one pair (or more if the prices are good, lol) to buy there, and you can always go online to see what they go for. I like to use google shopping. I can search for a specific brand or color, and it will send me to which ever site (Dressage Extensions, Equine Collections, Stateline Tack, even Smart Pak!) has what I want.

 I have these half chaps. Ride in them 2x/week, and the've lasted 5 years (I think - I don't remember exactly when I bought them, but it was at least 4 years ago (before I moved to TX), proabably longer. Some of the stitching (on the left leg's "patch") is coming undone, but other than that they look like they did when Igot them.

Plus, they are machine washable. (If you don't mind horse stuff in your washer, lol.)

 Since you are just taking lessons (I take dressage lessons as well, don't own a horse  )   I would get what is most comfortable right now since I can tell you that it will probably be awhile before you are ready to show anyways.   The only cavaeat is that I would ask your instructor if she/he cares.   Mind doesn't and I ride in breeches a pair of breeches with knee patches and paddock boots most weeks.