This discussion always gets a 98% vote for the UpLula. I own one also and I use it for one of my magazines but it isn't my favorite choice.
A couple decades before the UpLula hit the market, HKS was marketing a magazine loading tool. The first time I saw one in 1990-something, I looked at it and said "Hmmm, this looks like it will snap clean off." In 1994 I bought one to help load a fat double stack 9mm magazine, having bought my first 9mm handgun because the Clinton administration had targeted high cap mags.
That HKS Model 940 is still running like a champ and it's the one I like best. Where the HKS gets beat out by the UpLula is that the UpLula works for a slew of different magazines where the HKS only works properly for magazines of a similar dimension. In other words, if you bought the HKS 940, it would work great for your Hi-Power mags, S&W 59-series, Beretta/Taurus 92 and a slew of other magazines of similar exterior dimensions, but it's no good for a 1911 or a Glock mag or your Colt Mustang, etc etc.
But the UpLula works for dang near everything, and that's why folks love it so much.
I like the UpLula much,
much less because the design of the UpLula requires a hard surface to use well. Table top works best, you can "make do" with your thigh but it's less than ideal. The HKS doesn't need any flat or hard surface, it works wonderfully in your right hand with your thumb doing the work but with fantastic leverage.
So your easy answer is the UpLula, as any/every gun forum will quickly tell you at a 98% rate.
I believe the better answer is the HKS loader, of which I own probably 20. Definitely costs more this way... however a single one (which it sounds like you need!) runs about $12 last I checked.