I make catawba wine, and while I'm happy, it's definitely not the best and/or easiest wine to make taste good. It's acidic, and not very good on it's own. I used 65# of catawba grapes last year, and made 14 gallons of wine. One three gallon batch was only catabwa and it's tart and acidic. The others I played with- reducing acid, adding grape concentrate, etc, and it's ok. It's not a great wine, but it's ok. I also put it through MLF, and then cold stabilized it to precipitate more acid. It might age into a decent wine- it's just a tad over a year old now.
So, if it were me, I'd go with the sour cherry if you're only making one. Sour cherry juice makes a nice wine- but it does take a while. My sour cherry from last year is still harsh and astringent, and I added some honey (after talking with Ken Schram) to help smooth it out.
Jack Keller's website has recipes for both, and I would recommend reading the recipes and the techniques before deciding.
Catawba can make a good wine, but it takes more effort. Sour cherries pretty much do the job on their own, but need some time. Either way, plan on at least a year before considering bottling. Maybe more.