We did sonrise, and it was amazing for us and for ds. I don't know anything like as much about aba, but I can tell you why we chose son-rise instead.
Son-rise is fundamentally about establishing a bond with the child, then using that bond to motivate them to want to have social interaction, which includes verbal communication, but in a very'real' way. You establish that bond largely by whats called 'joining' them in their 'ism' , or stims, rather than judging or discouraging it. My understanding is that aba works more on a 'reward' basis, so the child does what you want, you give a 'reward' like a chocolate button or something.
There's a very detailed developmental model, so you work very, very explicitly on specific areas you want to encourage, whether that be language, flexibility etc.
son rise is also very much parent led, with volunteers, paid or unpaid, whereas I think with aba you hire professionals to work with your child.
I wonder of aba suits families who work more in that sort of way, more reward/ sticker chart kind of thing? We're not like that with our other dcs, so I dont think we'd really be likely to resonate or be able to sustain it. I think that's rEALLY important. You need to find what suits you, and ultimately they're both things that take a lot of commitment, we all want to do the best for our children.
The autism treatment centre of America, who teach son rise have loads of stuuff on their website, some specifically addressing the diffs. Here's one link.
www.autismtreatmentcenter.org/contents/other_sections/aba-vs-son-rise-program.php
Ds has gone from no language, very exclusive, to a madly chatty, funny boy who's intensely interested in 'what makes people tick'. Of course none of us know what would have been, but I really believe that he wouldnt be like this without the programme we ran. It was also one of the most joyous, lovely things I've ever done.
I hope that's of some help, I'm sure there'll be other people with much better knowledge of aba.