I have the Lat Pro bag and a Fade Crunch Box. I love them both.
The Lat Pro bag is great. you can cram almost 30 discs in there if you pack it right. but with all those discs you won't have room for any towels etc. I love the Pro bag for tourneys because I can pack in 20 some discs plus towels, golden retriever, sling shot, clip board, snacks, strap an umbrella and a stool to it and cram in an extra water bottle. the only downside to all this is it gets HEAVY. and the bag is kinda bulky in comparison to others.
I'm actually looking to get a bag in between the crunch box and the pro bag. the crunch box is great for a quickie but when I want to bring extra discs for try outs etc. I have to tote the big luggage and like I said it gets heavy since I tend to leave the non disc stuff in there all the time.
The Pro Bag is now $10 cheaper than when I bought it. so that is good news but if you aren't looking to put a lot of money into a bigger bag I would suggest the Fade Tourney. If they are built anything like the Crunch box it will be a tank for a good price. Hell I may get one just for kicks.