How many channels do you need - 8, same as your current setup?
Budget?
What type of music - still chamber ensembles?
Do you know what portable ADC will you use?
What are your requirements for "portable"? When I think of portable, I think of field portable, i.e. something I could schlep around in my bag all day on assignment (except that might get me fired as it has nothing to do with my real job!). To some folks, a rack on wheels is portable.
FWIW, the Edirol units are definitely prosumer, not pro, but the Oade Bros do some upgrades that make them sound mighty fine for what they are.
The Sonosax SX-M2 is warm and colored to my ears, with a nicely rounded low end. But not the choice if you want transparent, IMO. For transparency, I'd say Grace V2/V3. I've not worked with the 101s so I can't compare, but when I think portable, transparent preamp, I think Grace.