Big scoring disadvantage shooting 9mm in limited. Also, with the 19, it's a smaller gun with a shorter sight radius. You'd be better off with the 34 over the 19 but even better off with a 35 getting major power factor scoring.
I started with a G17 9mm (slightly bigger than the G19) & changed this year to G35 .40, I have no regrets for switching. Long targets are more accurate with the longer G35 & I donâ€™t take as big of a hit for â€œCharliesâ€ when I loose concentration on my front sight.
Only thing thatâ€™s wrong with it in my opinion is the scoring disadvantage. I shot a 5â€ M&P9 last year in limited and figured out real fast I couldnâ€™t shoot enough Aâ€™s fast enough to do worth a shit. I know a couple of fellas who have won or been top 5 combined overall with a 9mm in Limited but, that takes a lot of good hits in a short amount of time. Iâ€™m not anywhere close to that level so Iâ€™m back on the .40 bandwagon for now. That being said I have no regrets about shooting it last year or heartache about my performance or lack of. Just remember, itâ€™s a game and to have fun and be safe.
I'd probably use that tax return and set up your G19 for CO since thats what you're wanting to do anyway. the short slide really won't be a disadvantage in CO and you won't take the hit of shooting minor in a division dominated by major. you'd be more competitive in CO with the G19 than in Limited with a G34 I think.
A 19 isn't going to be the most competitive gun in any division simply because the sight radius is too short.
That said, unless you're trying to win matches, USPSA is mostly about developing your skills and making yourself a better shooter. A 19 will do just fine for that purpose. Shoot whichever division you like(limited if you hate reloads), and just focus on improving your skills and doing a little better each time out.
If you ever decide you want to be as competitive as possible, invest in a gun that fits the division requirements and gives you all the advantage you can get. A G35 or G24 would be ideal for limited(or a 2011 if you want to go down that road), and a G34 is optimal for production. For either case, you'll probably also be spending $200-500 on upgrades to get a gun that is truly competitive with what other people are using.