I've got Prolines...
Mine has settled now for well over a month and sits like your passenger side does now. Which was exactly what I wanted... It doesn't really look lowered.
I had the issue before with the front left sitting higher but my back right was slightly lower than the back left. With the springs fitted the back sits level but the front left is still slightly higher but it's hardly noticeable.
Make sure when you look at it it's parked on a perfectly level surface. My drive looks level but it isn't! Depending on where I'm parked on it the car looks completely different. It's only when I get into my work car park and walk around the car that it looks good all round.
There's nothing wrong with your car, look on ebay etc at all the 330/335 for sale - the front left sits noticeably higher on all of them. Strange; and shit!
Here.. The back doesn't sit that low normally, it's because it's on a slope. (further down my drive is flat if any confusion from above)
