Several questions to consider:
Do you expect to use the cart exclusively, or will you switch back and forth between a bag and a cart? If you're going to switch, do you look at moving and reorganizing your discs and course equipment as a hassle, or as a welcome chore? Thinking about those two could push you toward a dedicated cart, or a cart that carries an existing bag...
Do you tend to travel light, or travel heavy? Some carts have lots of space for "extra" items like coolers, zip-up packing bags, etc. It's my opinion that empty space tends to get filled up (because nature abhors a vacuum), whether that's extra discs, clothing, more beverages, whatever...My advice is if you want to stay light, don't buy a cart model with a lot of extra nooks and crannies.
Do you want a seat? Do you want it integrated (like being able to sit on the cart, or add a seat), or do you just want to carry a stool?
Does it matter to you if you want to push a cart (like Rovic) or pull a cart (like Zuca).
Lastly, looks do count for something. I've alwasy felt the Rovic looks a little "much" for disc golf (ok, a little bit too "old guy" there, I said it...I admit it's entirely personal bias).
I considered all of the above, and landed on a Zuca Backpack Cart LG.
