I don't usually get reviews for STPs and Packers for guys on the shorts/smaller end. I usually see them for guys who are average, tall, or bigger. I'm 5'6 and 115. Both short and skinny. Because of this I can't risk getting a too big packer or STP because it will most likely look like I have a boner or something. But I feel going too small might make the peeing aspect harder than it needs to be, though I really won't know cause I never really used an STP before.

So in terms of sizing, what might be a good size for guys on the smaller end of the weight and height chart?

I'm around the same height as you. I went with one of the Reelmagik basic 5inch packers. It looks really good and doesn't look ridiculous either. They also offer smaller sizes but personally I think 5 is perfect. As for STP I use Transthetics EZP (the only one that's worked for me). It's not big and gives you a good size in the bulge aspect and looks natural. The only thing is you have to wear it upwards can't wear it like a normal packer. The other nice thing about it is you only need tight underwear (boxer briefs for me) so you don't need an annoying harness.

I usually wear my packers with the shaft pointed either upward or sideways on towards my left leg, so that won't bother me either way. I tried pointing it downwards and it both looks weird, feels weird, and moves around way too much. Like I walk fast, basically jog everywhere, so I wear tight briefs all the time. Won't bother me. Thanks though, I'll look into it.

I do like RMs packers. They look really nice. I wish I can have their STP though. Now that looks super nice.