what youre looking for sounds very similar to my current setup, which is a 52v battery from em3ev, 1500w rear hub kit from ebikeling. i built on a slightly older (2004) cannondale aluminum full suspension mtb. all told, bike+motor kit+battery+a few other odds and ends cost me about $1900. unrestricted, i get a top speed of about 40 mph on a flat. i usually keep it restricted to 32 mph for regular commuting. if i know im gonna go further i restrict it more based on my needs. last week i rode across brooklyn, into manhattan, up a bit, and then back, a total distance of about 23 miles, which it handled good at 20 mph. i did drain the battery a bit more than i probably should have (was down to about 45v i think when i got to work) but hopefully doing that just once in a while isnt such a big deal. i was pulling a laden trailer for most of that, though, i stopped at costco on my way into manhattan. so, without that it would probably handle it easy.