Gdiapers are very expensive and not really much friendlier to the environment than disposables. They are not the same as the others. A doubler might work, but if you're going to do all of that, I'd personally rather use pocket diapers.
Probably the easiest in my opinion is the Bum Genius one size pocket. Many people will say the AIOs are easier (no stuffing) but I disagree, since washing and drying time are massively increased with AIOs. Bum Genius are aplix (like velcro) and snap down to accomodate smaller babies. They fit my large son almost until potty training. When soiled, I hold one end of the diaper and shake the insert into the wetbag - i never end up touching it at all. I wash, dry, and then take all the inserts and stuff the diapers right then. That way, they are ready to go when it's time to change a diaper.
I use Fuzzi Bunz as well, and love them. But for my husband and mother (and church nursery) I save the BG, since they're aplix and easier than snaps.
Thirsties AIOs are ok and it's cool that they are stuffable, but again, you have the washing and drying issues. I often found that the one we have needs to be washed more than once to get really clean, plus I have to turn it inside out, blah blah blah, and it's really not my favorite. IT's also much bulkier than the BG.
I also really like Happy Heiney's one size diapers (the sized ones are said to leak but the one size do not). They are also aplix, but fit my son still (he wears diapers at night) at 44 lbs. They snap down to fit my little daughter well too (and did at 15 lbs).
HTH! I've been using cloth for well over a year, and use pockets, AIOs, fitteds, and prefolds and pins with wool, so I've used lots of different things! I've experimented with different detergents to find what works best, I line dry AND dryer dry (at different times, but I like using the sun as a sanitizer). So if you have any questions, feel free to send me a message!!!
**ETA I read the other responses, and I'm pretty sure the first poster means the Bum Genius one size, not the all-in-ones. The all in ones (AIO) are the sized ones, where the one size pockets have a three rise snap to grow with your child. HTH!