Well this rather depends what you mean by 'one of the cheaper field recorders': from the perspective of top-end professional recorders such as the Nagra VI, SD Scorpio and SD 888, the SD Mixpre series recorders and the Zoom F series recorders are at the cheap end. Of these, I prefer the preamps of the Mixpre series recorders and, indeed, their functionality (which includes overdubbing: unusual for a proper field recorder), but there is no denying that the Zoom F6, for example, is very good value for 6 channels and has respectable preamps.

Cheers,

Roland