The R&T kits provide one of the best rides out of the box once installed, but only has about a ~20mm lowering range. If wanting to go lower, look into the Redwood, Mountain Pass or KW kits. Swapping for shorter springs is also an option if looking to go lower, depending if you drive with passengers/full cargo a lot you run the risk of hitting the bump stops.
Can't help on the eBay front, most times Ohlins won't honor warranty from kits purchased from eBay so double-check before pulling the trigger.