Sid,
my S1 3l has the standard exhaust & it and the engine are very quiet. To be honest after louder Mogs I really like it.
John
I can certainly appreciate the appeal of the S1, and if I can't find a suitable 3.7 (are they referred to as the S3?), then I may have to reconsider my options.
The lack of ground clearance in the S1 is an issue for me. In my +4 I've managed to get nearly 120mm of clearance by shortening the rebound springs and changing to 195x65 tyres, which has given me far greater confidence to go anywhere without running the risk of it grounding. So now, roadside verges, rutted country lanes, raised ironwork and those bleedin' speed humps hold no fear! So I'd be very reluctant to change to anything that I felt compromised things.
I know fitting a Mulfab sump helps, but I'm not sure that this improves things sufficiently, but I'm willing to be told otherwise by those in the know. Who knows, I might be tempted by an S1 after all...