That will be interesting.
First time I tried any DS emulation on my desktop was choppy and laggy (around pre-2009). Got bored/forgot about DS emulation and I think like 2010 tried it again and it was less choppy and laggy...noticeably less, but still apparent.
I dunno if they've perfected DS emulation for desktops now, even. Last I used was NO$GBA...you had to get firmwares and whatever or something (seriously...been a long time and I barely played haha).
Desktops (back then) and iPads were/are certainly powerful enough...but iPad emulation is contingent on desktop emulation being close to perfect (by that I mean playable).