I had a 357 LCR - traded it in on a S,with Model 36 J frame. I used speed loaders though on the LCR - and yes, it can be tight The trick is to angle it in to the cylinder and release - with practice you can learn to drop 'em right in without a problem.
The speed losers I had purchased for m LCR are marked HKS 35.
I kept them as they work on my Smith 36 J frame, but actually, I much prefer carrying either a single or a double "drop pouch" as for my CCW purposes, the drop pouch is flat on the belt and doesn't stick out like a speed loader pouch. In my normal single drop pouch I can fit 7 cartridges in.
My biggest problem with the speed loaders I have is that once the cartridges are locked in, all it taks is a turn of the knob and they drop. I just went in and checked the two I have which were loaded and in a double nylon belt pouch with velcro retained nylon flap covers. I reached in, gently grabbed the knob which is what you would do if needed, and when I pulled the speed loader out - the cartridges remained in the pouch. Maybe a different brand of speed loader would work better - but I personally don't trust the ones I have just because it doesn't take much of a turn of the knob and the cartridges drop.
I've tried strip speed loaders - speed strips - and I didn't care for them either. That's why I pesonally prefer a drop pouch - chances are I would never be in a SD situation that required a reload - but the single pouch does give me another cylinder full (5) plus a spare 2.
I'd suggest that before you buy a speed loader, it might be a good idea to go to a LGS and have them show you what they have so you could try them out. Everybody has different preferences and different things that work best for them. Best of luck to you!