Had one for five years, foolishly sold it to get a Fatboy. Stage one with open pipes, solo seat, 16" apes, forkbrace ( it did make a wee bit of difference ), etc. Rode it all year round. Front brake is pants, but if you keep on top off it, it can do the job ( add braided hoses and don't skimp on the quality pads ). Rear brake fine. Riding position was good, longest covered in one day was about 340 miles. Good gas milage on the motorway, but I had a small tank ( 2 gallons ) on mine so frequent top-ups needed. Oil consumption wasn't a problem.
Parts can be expensive but the second-hand market is very good and if you punt around you can get some real cheap parts to keep you going ( buy you service items from the states with a mate or two, get 'em for half the UK, including the postage. Change your oil frequently, it does make a difference. Cover the external parts that can corrode quite quickly with Corrosion X ( used in the aircraft industry ). If you don't want to buy chrome parts you can once again get the standard parts very cheaply, as most people buy shiney bits and biff the standard finish.
Loved it, would have one again any time. Don't let Harley snobbery put you off. Some think that Sportsters are not "big" or "real" Harleys. This is B.S. Think of it more as an evolution from the big old British bikes in their day.
Best off all, get an older one ( post '91, with the five speed box. Trust me, it makes a difference on motorways! ) for £2500, ride it for a while, if you don't like it you will get your money back on it. Cheers!