if you're lookign for something like a modelling amp, i believe that the spider, the cube30, and the vox are the ones you'd be looking at.
once had a johnson modelling amp, some time ago, and it gave me a lot of problems. its now lying in my backyard back home in indonesia.
my 5cents worth, i'd still tell you, get an 'analog' amp. it will sound sweeter like that. yeah. more costly for some, but its gonna be worth the investment. yupz.