My first aftermarket KTM seat was an SDG for the '01 520 MXC, and I'm not sure it was much of an improvement at all.
Still rock hard, still narrow... the best was a Guts Racing that Saul put on the 525.
That long Mt. Withington loop down there about did me in on the stock 310 seat.... then I had the bonus of riding Mark's Sherco and it's plush suspension and
Renazco seat. I didn't want to swap back
First thing I did when I got back was send my seat off and took the bike to his suspension guy...
I finally got around to putting the petcocks, fuel pump, and bypass valve (two large openings on the tank aside from the two petcocks) on the IMS tank.
When I went to slosh test for weeps....there was no IMS cap - never missed it being gone until I realized just now the stock tank (Acerbis) has a different diameter opening than the IMS.
So I sent JGT an email asking for a cap.