Yes, the GW-8 has ON BASS.
And has anyone actually TRIED a Sonic Cell editor on the GW-8? It's voice architecture looks VERY like a SC to me. As to whether you can actually STORE the edits, not so sure there...
The thing for me has always been, as a live instrument, Roland have always provided pretty well tweaked sounds in the first place, and a HUGE selection of synth sounds, both pad and lead. Along with the usual 'offsets' to voice programming (the usual stuff - cutoff, resonance, envelope and LFO offsets), you can get pretty much anything you'd need for a live 'approximation'. And, if detail voice editing of sounds is your MAIN priority, then other Roland products can do this, and better. You really have to play with the huge selection of sounds Roland provides before you decide that this product actually NEEDS detail voice editing. I'm as picky about my sounds as the next guy, and so far, with the same editing sparsity as the GW8, my G70 hasn't disappointed me yet.
Keeping costs down for a budget piece of kit like this has to involve SOME kind of compromise, doesn't it?

At least they have addressed the sparse (you might say non-existent

) style editing of the earlier software version... in fact, leapfrogged over many much more expensive arrangers with detail editing and style creation ON-BOARD, something that several other arrangers need computer software to achieve.
And the drum kits definitely have that Roland 'live' feel to them and now can do multiple kits in a style. This one is one to watch out for...