For .38/.357, I like Safariland speedloaders. I've used their Comp I loaders for my 642 for several years. They're probably the easiest to use: Insert rounds, push, done. Jet Loaders and SL Variants operate the same, but I don't have experience with them, and, as was mentioned previously, the SL Variants are very difficult to come by. In my experience, the Safariland loaders, at least the Comp Is I've used, are durable, having been dropped multiple times (

), including on concrete floors, without spilling rounds or losing functionality. I've read about people intentionally throwing them against walls, still holding their rounds and releasing them as designed.
Their one downside is if you like Split-Six-type carriers, where the loader straddles the belt with rounds on each side. With Safariland loaders, the release mechanism rides on the top edge of the belt in these carriers. Enough downward pressure, and you'll be picking up rounds off the floor.
HKS are fine loaders, but after having used them both in practice and on-duty as an armed guard, I don't like them. You have to insert the rounds, hold the cylinder so it doesn't move, then twist the knob to release them. I prefer the simplicity of the Safariland loaders.
Don't have any experience with .44s, other than knowing that HKS makes loaders for some .44s. I don't know about Safariland.
Strips are a good option, and are available in both .38/.357 and .44. Bianchi was the original Speed Strip, if I'm not mistaken, but I prefer Tuff Products Quick Strips because they have more options with regard to round count and color. They can wear out, crack, and break, but it can take years for that to happen, depending on usage and what kind of climate/temperatures they're exposed to. But they're not expensive, and I consider them a consumable item, so I make sure I have at least a few on hand and just replace the ones that wear out or break. Regular inspections and tests are a good idea, with strips or speedloaders.
I'll echo the sentiments of others who suggested getting one of each type and work with them to see what suits you best. When you decide on the one you like, practice, practice, practice.
Just my opinion.