Lees Avionics at Wycombe Air Park have just fitted the British Airways Flying Club PA28-236 Dakota with a Garmin G600 and the 430 was upgraded to WAAS at the same time (needed to drive the G600).
Looks brilliant, not had a chance to fly it yet though. First customer installation in Europe IIRC. Just go for it - it's only money and good avionics should put some value on the aircraft and make it more saleable if the need be.