I also have an 8 month old and we've been EC'ing since birth. Here's what I've learned so far:
Training pants are great because they are easier to slip up and down and facilitate frequent potty offering. And, at this age, my dd does not want to be laid on her back to fuss with snapping on a diaper (luckily she stands very well and we do everything standing up!) But the downside is you don't really want to have a poop miss in them because it would be messy to get it off. So I would use them when I knew she wouldn't poop, and for going out (since about 4 months, I think). We just began a full time move into training pants. My favorite ones are made by
Bongo Baby. However, they are pretty pricey ($18-$25). I bought most of mine at
EC Wear
My favorite diapers have been her Kissaluvs. They are a cotton terry, and you and your LO will
definitely know when he's wet, as long as he is coverless. I have never had anything leak out of them, they have worn like iron and were not too pricey (I bought a lot of mine gently used and on clearance). I think they are around $12 new. You will definitely want to change these after every wet, as you would with training pants, but that's pretty necessary for successful EC'ing, IMO. I think any fitted diaper made out of mostly cotton will work for you. Really, the only difference between her Kissaluvs and her training pants is that I can snap the diapers on and off if I need to. There are also training pants made with side snaps. I have a nice pair made by
Continuum-Family. Deirdre also makes a very nice training pant similar to the Bongo Baby. But again, these are pricier than the diapers.
If I were you, I'd move full time into cloth diapers, take the cover off unless it's really not ok to have wet pants (like maybe in the car seat), and get a few trainers to play with until you are confident that the poops are going in the potty.
Good luck!