for that reason i picked up 2 Mus...
I know exactly what you are talking about..... i picked up two 2007 Dahon Mu P8 .... i liked the 2007 better than the 2008 - the saddle is wider, the RD is Sram and the folding mechanism is easier to use IMHO.
My wife feels her saddle should be adjusted and my words to you my friend is first try to understand why and where she feels uncomfortable.... When i first got the bike i felt like the saddle is way to big and wide for me but after a few rides and minor adjustment i have finally found the sweet spot... there are a few adjustment you can make to the saddle so first try to switch seats with her and see if it helps.... maybe it's just the saddle or maybe more than that. You can also put the bike side by side and try to adjust the Mu like the Mini (you know- handlebar, seat post, saddle etc....) if this doesn't work start with some upgrades like Big Apple tires and maybe a new saddle.
After riding my Mu P8 for a few times i feel it is super fast and smooth, i keep up with full side bikes with no sweat at all. It doesn't fold to a tiny package but it is small enough to carry.
Overall i think the Mu P8 is a great bike, keep in mind it does feel more like a sporty touring bike, probably the wheels and frame giving the rider that feel, i am not sure about the Mini but when my wife and i tried the Curve we felt it is more comfortable but after adjusting the Mu like the Curve it was almost perfect... i think the Big Apple tires are great but at the same token they are way slower than the Marathon Racer.