As far as browsers for classic amigas go, they're functional, but definately considerable room for improvement. The 3 main options Id suggest are probably IBrowse2.4, Aweb, and Voyager. Apart from that there's also Netsurf, which while a little quirky works reasonably well, although needs a gfx card (sdl based). Additionally there's a port of OWB, but not only is it sdl based, but its even slower than netsurf, and is probably unusable on anything but an emulated 68k cpu. That said, and despite being rough around the edges I find it's quite useful on my amithlon box and is very fast once the pages have fully loaded.
An indirect route is to use on the 68k mac os browsers inside shapeshifter or similar. Theyre obviously pretty outdated as well, but do offer a little bit more modern a browsing experience in terms of page rendering. Netsurf and iCab are probably the 2 best choices for that route.